Occupational Medicine Prof. Francesco S. Violante Chemical agents and pesticides.
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Transcript of Occupational Medicine Prof. Francesco S. Violante Chemical agents and pesticides.

Occupational MedicineProf. Francesco S. Violante
Chemical agents and pesticides

Chemical AgentsSolvents Organic compounds, normally liquid at ambient temperature, that
can dissolve several organic substances, which are not water-soluble, without modifying their properties
The solvents used in industry belong to different classes of organic substances:
Aliphatic Hydrocarbons saturated – alkanes or paraffins (C-C and CnH2n+2) unsaturated – alkenes (C=C and CnH2n) and alkynes (C≡C CnH2n-2)
Alicyclic Hydrocarbons (Chains of C atoms bond together to form rings) cycloalkanes (CnH2n) cycloalkenes (CnH2n-2) cycloalkynes ( CnH2n-4)
Aromatic Hydrocarbons or arenes (having one or more benzene rings) monocyclic or mononuclear polycyclic or polynuclear
halogenated derivatives of aliphatic and aromatic hydrocarbons Alcohols and glycols Aldehydes and ketones Esters and ethers of alcohols and glycols Amides

Federchimica 2005: solvents widely used in Italy
chetoni; 180000; 25%
aromatici; 150000; 20%
alifatici ; 130000; 17%
esteri; 120000; 16%
alcoli; 100000; 13%
clorurati ; 70000; 9%
chetoni aromatici alifatici
esteri alcoli clorurati
Consumption in Italy Significant examples
ketones
180.000 T/y
ACETONE and CYCLOHEXANONE
aromatic solvents 150.000 T/y
TOLUENE and XYLENE
aliphatic solvents 130.000 T/y
CYCLOHEXANE and HEPTANE
esters
120.000 T/y
BUTYLACETATE and ETHYLACETATE
alcohols
100.000 T/y
BUTANOL and ETHANOL
chlorinated solvents 70.000 T/y
METHYLENE CHLORIDE and DICHLOROETHANE
Chemical Agents

Aromatic Hydrocarbons: industrial usesPERCENTAGE USES
50% Products: Varnishes Diluents Inks Perfumes
20% Rubber industry
20% Pesticide industry
9% Metal degreasing and dry-cleaning
1% Explosive industry
Chemical Agents

BENZENE
Clear, colourless and highly flammable liquid, with typical pungent and aromatic odour;
Extremely volatile at ambient temperature (vapour tension=100 mmHg at 26.1C);
Scarcely soluble in water and highly soluble in organic solvents; it is a powerful fat solvent
Chemical Agents

BENZENE
Occupational Exposure
Workers engaged in the oil processing industry
Distillation and distribution of petrols (pump operators)
Chemical Agents

BENZENE
Exposure
Use of benzene and its analogues in work
processes: Decree 10th December 1996, no. 707
“Viene prescritto il divieto di uso di benzene e di sostanze e
preparati contenenti benzene in concentrazione pari o
superiore allo 0,1% della massa: da tale divieto sono esclusi i
carburanti di cui al D.M. 214/88, le sostanze e i preparati
adoperati in processi che non permettono l’emissione di
benzene oltre le quantità prescritte, i residui previsti dalla
normativa sui rifiuti”
Chemical Agents

BENZENE
Extra-occupational Exposure
Natural sources (e.g. Volcanic activities) Tobacco smoke (active and passive) Indoor pollution due to usage of domestic
products Motor vehicles emissions
Chemical Agents

BENZENE
Extra-occupational Exposure
Air quality objectives: Decree 2nd April 2002, no.60. The Ministry of Environment andTerritory Protection in agreement with theministry of Health:
“Stabilisce per gli inquinanti biossido di zolfo, biossido di azoto eossidi di azoto, materiale particolato, piombo, benzene e monossido di Carbonio: valori limite e soglie di allarme\ margine di tolleranza e modalità di riduzione\ termine entro cui si deve raggiungere il limite stabilito\ criteri per la raccolta dati, tecniche di misurazione….\ soglie divalutazione\ modalità di informazione al pubblico\ formato per la comunicazione dei dati”
Chemical Agents

Annex V: Benzene threshold limit value
Averaging Period
Limit Value
Tolerance Margin
Date by which limit value is to be met
Limit value for the protection of human health
Calendar Year
5 µg/m3 100% of the limit value, i.e. 5 µg/m3, on the entry into force of Directive 2000/69 (13/12/2000).
This value was reduced as of January, 1, 2006 and every 12 months thereafter by equal annual percentages to reach 0% by 1 January 2010
1st January 2010
Chemical Agents

BENZENE
Exposure limit valuesIn 2000, ACGIH proposed:
a TLV-TWA of 0.5 ppm (1.6 mg/m3)
a TLV-STEL of 2.5 ppm (8 mg/m3)
Biological exposure indices (BEI) have been
proposed for occupationally exposed subjects: 25 μg/g creatinine for SPMA 500 μg/g creatinine for t,t-MA in urine samples
collected at the end of the work shift
Chemical Agents

BENZENE
Toxicokinetics Absorption: mainly by inhalation, but also by
transcutaneous route Distribution: adipose tissue and bone marrow Metabolism and elimination after absorption:
0 to 50% of the absorbed benzene is excreted unchanged in the exhaled air, (in relation to metabolic activity and body fat)
A small quantity of benzene (<1 %) is excreted unchanged in urine
The remaining part is metabolised
Chemical Agents

BENZENE
Toxicokinetics
Chemical Agents

BENZENE
Acute Toxicity
Skin irritation and irritation of ocular and respiratory mucosae
CNS: excitement followed by worsening depression (depression worsens as exposure increases)
Myocardium: arrhythmias leading to ventricular fibrillation
Chemical Agents

BENZENE
Chronic Toxicity
Hemopoietic System:
Modifications of the hematic crasis, including pancytopenia
Myeloblastic leukemia and hemocytoblastic leukemia
Chemical Agents

BENZENE
Toxicological MechanismsThe carcinogenic effects of benzene are mainly induced by itsmetabolic intermediates, which can act by:
Inhibition of mitosis associated with inhibition of mitotic spindle formation
Disrupting the covalent bonds of proteins, including hemoglobin, and DNA
Inhibition of DNA polymerase and chromosome damage (including aberrations)
Chemical Agents

BENZENE
Biological Monitoring of Exposure Relationship between organic and total sulfates in
urine: this was the first proposed test, which was subsequently abandoned due to its poor sensibility and specificity
Urinary phenol concentrations do not correlate with benzene exposures below 10 ppm. For this reason, urinary phenol is not suitable as a biomarker of exposure in current industrial settings
Benzene in blood: although able to detect exposure, benzene in blood is not a useful biomarker of exposure extent, because its hematic concentration rapidly decreases after the end of exposure
Benzene in inhaled air reflects the extent of a recent exposure
Chemical Agents

BENZENE
Biological Monitoring of Exposure
Urinary benzene: benzene concentration in end-shift urine reflects exposure during the work shiftUrinary trans,trans-muconic acid (t,t-MA): Urinary trans,trans-muconic acid concentration in end-shift urine is an index of low-level exposure to benzene (≥0.5 ppm) for equal levels of exposure, t,t-MA urinary concentrations vary widely Hypothesis: genetic polymorphism\ other absorption sourcesUrinary S-phenylmercapturic acid (SPMA):It is equally sensitive, but more specific than t,t-MA and is not affected by dietary factors
Chemical Agents

TOLUENE
Colourless, flammable liquid, with typical aromatic odour
Boiling point: 110.4 °C Scarcely soluble in water and soluble in
alcohol, ethyl-ether, benzene, chloroform It is less volatile than benzene, but it
produces flammable vapours
Chemical Agents

TOLUENE
Occupational Exposure
Solvent for oils, resins, natural and synthetic rubber, tar, asphalt;
Thinner for paints, varnishes and inks; Manufacturing of explosives, colouring
agents and phenol synthesis; Employed in the production of car and
plane fuel for its detonation properties
Chemical Agents

TOLUENE
Extra-occupational Exposure
Environmental pollution caused by traffic Contaminated waters Tobacco smoke
Chemical Agents

TOLUENE
Toxicokinetics
Absorption and distribution:same as for benzene
Metabolism and elimination: 20% is excreted unchanged in exhaled air A small amount is excreted unchanged in urine The remaining part is metabolised in the liver
Chemical Agents

Toluene is subsequently converted into benzoic acid andhippuric acid (about 80%), which are excreted in urine with
minor amounts of o-cresol.
Metabolism and elimination:It is less toxic than benzene and has no mutagenic effects; (unlike benzene, which is oxidized at the ring) it is primarily oxidized at the side chain: P450 monooxygenase enzyme P450 displays high selectivity for the methyl group of toluene. Oxidation produces few epoxides, which are responsible for the carcinogenic effect. Moreover, the small quantities of epoxide produced are further reduced by conjugation with glutathione, by spontaneous phenol rearrangements or by diol enzymatic hydrolisis.
Chemical Agents

TOLUENE
Acute Toxicity
Acute irritation of the skin and irritation of the mucosae with which it comes to contact
CNS: asthenia, dizziness, drowsiness, balance and motor coordination disorders
Isolated cases of sudden death after inhalation
Chemical Agents

TOLUENE
Chronic Toxicity
Skin irritation Dyspeptic disorders and abdominal pain,
intolerance to alcohol, symptoms of the CNS Hepatotoxicity Leukemogenic and carcinogenic effect?
Chemical Agents

TOLUENE
Biological Monitoring
Toluene in blood shows good correlation with environmental exposure level and urinary concentration of hippuric acid
Ortho-cresol in urine is a sensitive index of exposure, but shows a wide range of interindividual variability
Hippuric acid in urine is a fairly sensitive index when measured in end-shift urine, although the interpretation of personal monitoring is uncertain
S-benzyl-mercapturic acid (a BLV is not yet available)
Chemical Agents

TOLUENE
Exposure limit values
In 2000, ACGIH proposed:
a TLV-TWA of 50 ppm (188 mg/m3)
The following biological exposure indices (BEI) have
been proposed for occupationally exposed subjects: 0.5 mg/l for end-shift urinary o-cresol 1.6 g/g creatinine for end-shift urinary hippuric acid 0.05 mg/l for toluene in blood collected before the
last shift of the working week
Chemical Agents

XYLENE
Colourless liquid, with a typical aromatic odour
Highly soluble in alcohol and ether, insoluble in water
Commercial formulations contain a mixture of its three isomers (para-, ortho-, and, to a large extent, meta-xylenes) and other aromatic hydrocarbons as possible impurities (ethylbenzene, benzene, toluene)
Chemical Agents

XYLENE
Occupational Exposure
Rubber, colouring and varnish industry Graphic industry Degreaser for dry-cleaning of fabrics Raw material in the synthesis of plastic materials
and synthetic fibres Production of aviation fuel Solvents for paraffin, Canadian balm, polystyrene
(histology laboratories)
Chemical Agents

XYLENE
Extra-occupational Exposure
Contaminated waters (close to fuel collection and storage areas)
Tobacco smoke, active and passive
Chemical Agents

XYLENE
Toxicokinetics
Absorption and distribution:same as for benzene
Metabolism and elimination: Partially excreted unchanged through respiration; during
desaturation (after end of exposure), about 5% of absorbed hydrocarbon is excreted through the lungs and a minor fraction is excreted in urine (about 1%)
The remaining part (95%) undergoes oxidative biotransformation mainly to methylhippuric derivatives (methylbenzoic acids)
Chemical Agents

Metabolism and elimination: In humans, these substances are mainly conjugated with
glycine, forming ortho-, meta and para-methylhippuric acids, which are subsequently excreted through the urinary system
Non-conjugated methylhippuric derivatives are quickly excreted through two different metabolic routes: a relatively rapid one (elimination from the muscles) and a slower one (elimination from adipose tissue); excretion is considered to be complete after two days from the end of exposure
Chemical Agents

XYLENE
Acute Toxicity
Same effects of toluene Severe effects are rare due to the low
olfactory threshold (0.17 ppm) and to the easy detectability of highly irritating vapours
Chemical Agents

XYLENE
Chronic Toxicity
Alteration of hepatic and renal function Irritative lesions of the skin and mucosae CNS Myelodepressive effect
Chemical Agents

XYLENE
Biological Monitoring
Xylene in blood End-shift urinary xylene End-shift urinary methylhippuric acid
Chemical Agents

XYLENE
Exposure limit values
In 2000, ACGIH proposed: a TLV-TWA (mixture of isomers) of 100 ppm(350 mg/m3)
Biological exposure index (BEI) suggested:
methylhippuric acids ≤ 1.5 g/g end-shift
urinary creatinine
Chemical Agents

CYCLOHEXANE (C6H12)
Aliphatic solvent, colourless liquid at 25°, highly flammable
Pleasant, sweet odour, similar to that of petrol and chloroform (pungent when impure)
Insoluble in water
Chemical Agents

CYCLOHEXANE (C6H12)
Industrial Uses Benzene hydrogenation and oil fractioning
processes Glue solvent in the footwear industry Solvent for fats, oils, waxes and resins in the
chemical and cosmetic industry Solvent for colours paintwork Printing materials It has replaced benzene and toluene in several
manufacturing processes It was present in petrol vapours in 1983 (NOES
Survey 1983)
Chemical Agents

CYCLOHEXANE (C6H12)
Toxicokinetics
Absorption Pulmonary: predominant route (22-34% of inhaled dose,
according to studies conducted with personal samplers) Cutaneous: in theory, given its high liposolubility, it is not
characterised by a “significant percutaneous absorption, unlike other substances with similar chemico-physical properties like n-hexan and n-heptane”
Gastroenteric: it can be well absorbed
Chemical Agents

CYCLOHEXANE (C6H12)
Toxicokinetics
Distribution It tends to accumulate in the adipose tissue, where it
reaches higher concentrations (up to 20-fold higher) than in other tissues including the CNS
hematic concentration values are similar to alveolar values (consistently with the blood/air partition coefficient close to unity)
Biotransformation Degradation by oxidative processes leads to the formation of
molecules with hydroxyl radicals, which are subsequently conjugated to glucuronic acid
Chemical Agents

CYCLOHEXANE (C6H12)
Toxicokinetics
Elimination It is mainly excreted in urine (cyclohexane <1%,
cyclohexanol 0,1-0,2%, and cyclohexanediols 20-40%) and, to a lesser extent, via the pulmonary route
Chemical Agents

CYCLOHEXANE (C6H12)
Acute exposure
At high concentrations (300 ppm), the substance and the vapour are irritating to the eyes and mucosae
It is irritating to the respiratory tract. At higher concentrations, dumbness, nausea,
vomiting, loss of coordination and other narcotic effects can occur
If the liquid is ingested, aspiration into the lungs can lead to chemical pneumonia.
Chemical Agents

CYCLOHEXANE (C6H12)
Chronic Exposure
Skin: dryness, exfoliation, fissuring dermatitis, alteration of lipid cutaneous film
No evidence of hematological alterations similar to those provoked by benzene
Chemical Agents

CYCLOHEXANE (C6H12)
Biological Monitoring
Urinary 1,2 and 1,4 cyclohexanediols are still well detectable at 72 hours after exposure (the concentration of 1,2 cyclohexanediol is almost twice as high as that of 1,4 cyclohexanediol)
Urinary cyclohexanol (glucuronated form), which is is no longer detectable at 6-8 hours, is not useful for biological monitoring
End-shift alveolar concentration is 10-30% of environmental concentrations, used to document point exposures
Chemical Agents

CYCLOHEXANE (C6H12)
Biological Monitoring
In 2006, ACGIH proposed an exposure limit value:
a TLV-TWA of 100 ppm (344 mg/m3)
Chemical Agents

ACETONE (C3H6O)
Alicyclic ketone, colourless liquid, miscible in water and easily flammable
Industrial Uses
Chemical synthesis industry (solvent for rubber, plastics, lacquers, silk, fibreglass, resins, cellulose, cellulose acetate, glues, artificial leather, synthetic fibres etc.)
Chemical Agents

ACETONE (C3H6O)
Toxicokinetics
Absorption pulmonary: 70-80% of total inhaled amount Cutaneous
Distribution Uniform, generally more soluble in blood It does not accumulate in the adipose tissue
Chemical Agents

ACETONE (C3H6O)
ToxicokineticsBiotransformation Exogenous acetone is metabolised in various tissues, mainly
in the liver, where it is converted to acetic acid and isopropylic alcohol (excreted in urine)
Elimination (clear discrepancies) Primarily exhaled as CO2 or unaltered (dose-dep.) Renal route (minor pathway) both as acetone and metabolites Poor cutaneous elimination
Chemical Agents

ACETONE (C3H6O)
Acute Toxicityingestion, inhalation and extensive skin contact Neurological disorders: CNS depression of different
severity: excitement, headache, asthenia, sedation and numbness up to loss of consciousness
Cardiovascular disorders: tachycardia and hypotension
Respiratory disorders: irritation, respiratory depression and death can occur after high exposures
Eye irritation Gastrointestinal disorders: nausea, vomiting,
hematemesis due to severe cutaneous and inhalatory exposures
Chemical Agents

Renal damage Hepatic damage Electrolytic disorders: metabolic acidosis
Dermatological disorders: erythema and irritation, nail fragility
Metabolic disorders: hyperglycemia, ketonemia and diabetic-like ketoacidosis. Hyperglycemia, polyurea and polydipsia can persist for several weeks
Development toxicity: it has no tetratogenic effects on experimental animals. Spermatogenesis, morphology and sperm motility and number were tested.
Genotoxicity: sex chromosome loss or non-disjunction during S phase, also evident in cytological studies on fibroblasts
Chemical Agents

ACETONE (C3H6O)
Chronic Toxicity
No episodes of low-concentration chronic inhalation have been reported, causing severe effects in humans
Skin: alteration of lipid cutaneous film
Hematologic disorders: can produce effects on blood and bone marrow
Chemical Agents

ACETONE (C3H6O)
Biological Monitoring Acetone in end-shift urine
Exposure limit values In 2006, ACGIH proposed:
a TLV-TWA of 500 ppm (1188 mg/m3)
a TLV-STEL of 750 ppm (1782 mg/m3)Classified as A4 (i.e., not classifiable as a human carcinogen)
BEI: 50 mg/l (non-specific)
Chemical Agents

Parasiticides
Plant Protection Products
Pesticides

Plant Protection Products
Active substances and preparations intended for:intended for:
Plant or plant products protection against harmful organisms (insects, acari, nematodes, fungi, etc.) → parasiticides and pesticides
Promoting and regulating plant growth processes. Fertilizers are excluded, because they mainly act on the soil (phytoregulators)
Preserving plant products (e.g. cereals and feedstuff) before industrial processing. Preservative are excluded
Killing undesired plants (weed killers or herbicides)

Plant Protection Products
Since ancient times, man has developed strategies for controlling parasites and insects (e.g. Sulphur as fungicide, strychnine for rodents, arsenic compounds as herbicides or insecticides…)
The synthetic chemistry era begins in the 30s, and several new compounds are introduced
(alkylthiocyanate insecticides, dithiocarbamate fungicides , until DDT)

Plant Protection Products
Despite the risk connected with the use of plant protection products, the cost/benefit ratio is favourable:
They protect crops, increasing product quantity and quality
They allow control of severe epidemics, killing vector insects

Pesticides
Any chemical, physical or biological agent, which is able to kill insects, animals, plants or microorganisms that are undesired or harmful to human beings
(Klaassen CD. Casarett & Doulls’s Tossicologia. I fondamenti dell’azione delle sostanze tossiche. EMSI Roma 2000)

DISEASES TRANSMITTED TO HUMANS BY PATHOGENS THAT CAN BE CONTROLLED BY PARASITICIDES
DISEASE VECTOR ETIOLOGIC AGENT
Malaria Mosquito (Anopheles) Plasmodium Malariae.
Filariasis Mosquito (Culex, Aedes, Anopheles)
Wuchereria Brancofti
Yellow Fever Mosquito (Aedes aegypti) Group B Arbovirus
Viral Encephalitis Mosquito Arbovirus
Petechial Typhus Louse Rickettsia Prowazekii
Bubonic Plague Rat flea Pasteurella Pestis
Rocky Mountain Fever Tick Rickettsia Rickettsii
Pesticides

Consumption
40% North America (1 million kg)
25% Western Europe
35% Other countries
2-3% Italy
The EPA (Enviromental Protection Agency) established an A.D.I. (admissible daily intake)value=NOEL/100 per molecule
Pesticides

Occupational Exposure
Chemical industry workers responsible for the production of plant protection products
Farm operators responsible for phytosanitary treatments
Public health operators responsible for disinfestations
Workers dealing with biological degradation products: leather, paper, wood and varnish industry
Pesticides

Extra-occupational Exposure
Intake of contaminated food and drinks Living in the proximity of agricultural areas and
areas subject to public health interventions
Domestic use (e.g. gardening)
Slow release of parasiticides from treated products (e.g. pentachlorophenol)
Pesticides

Absorption Inhalatory route(main absorption route for chemical industry operators)
Cutaneous route(main absorption route for farm workers)
Oral route(main absorption route for extra-occupational exposure)
Pesticides

Intoxications: WHO data
Developing countries: 3 million pesticide intoxications registered every
year, 220.000 of which are lethal With regard to non-registered cases, it is likely
that 3% of farmers (830 millions) experience one episode of intoxication a year
Pesticides

INTOXICATIONS IN AFRICA
CountryPopulation (millions)
% of workforce employed in agriculture
Cases of pesticide intoxication per year
Sudan 24 80% 384.000
Tanzania 23 85% 368.000
Kenya 22 80% 350.000
Uganda 17 80% 272000
Mozambique 15 70% 240.000
Cameroon 11 80% 175.000
Zimbabwe 10 80% 160.000
Ivory Coast 10 80% 160.000
Malawi 8 85% 128.000
Senegal 7 80% 112.000
Mauritius 2 75% 3.200
Pesticides

INTOXICATIONS IN ASIA
The cases if intoxication per year in Indonesia are estimated to be 30.000, 2.400 of which require hospitalization
In Thailand, the number of cases in 1985 was 4.046, 289 of which were lethal
In Malaysia, the 7% of farm workers faces one intoxication every year
In 1995, pesticide intoxications were the main cause of death in hospital in six rural districts (about 3 million inhabitants) of Sri Lanka
Pesticides

INTOXICATIONS IN SOUTH AMERICA
Between 1980 and 1986, 3.300 hospitalizations and 429 deaths (60% caused by paraquat) were registered in Costa Rica.
In a study conducted in 1988 on a region of Nicaragua, out of 3.300 treated cases, only 1.143 were registered in the Regional Register of Pesticide Intoxications, with an assumed underestimation of 65%
Pesticides

Classification
Parasiticides can be classified according to:
Their target (functional classification)
The chemical structure of their active principle (chemical classification)
Toxicity (toxicological classification)
Pesticides

Functional Classification
Insecticides
Weed killers or herbicides
Fungicides or anticryptogams
Rodenticides
Acaricides
Molluscicides
Nematocides
Pesticides

ClassificationDL 50 (mg/kg)
Oral Cutaneous
Very toxic (T+) ≤25 ≤50
Toxic (T) 25</≤200 50</≤400
Harmful (Xn) 200</≤2000 <400
Toxicological Classification
Current Classification(also based on subacute and chronic toxicity)
Pesticides

Toxicological Classification
In Italy, very toxic, toxic or harmful plant protection products can only be bought by professional certified users (owning a licence provided for by D.P.R. 1255/68)
Interview aimed at assessing knowledge of the hazards associated with the possession and use of plant protection products
Pesticides

Insecticides
Phosphorganic or organophosphoric Compounds
Organic-nitrogen compounds
Chloro-organic or organochlorinated compounds
Vegetable insecticides
Organic sulphur-nitrogen compounds
Insecticidal oils
Inorganic compounds

Phosphorganic or Organophosphoric Csesters of phosphoric, orthophosphoric, pyrophosphoric, thiophosphoric, dithiophosphoric acids with an inorganic radical: Phosphates Thiolophosphates Thionophosphate Dithiophosphates Pyrophosphates Phosphonates Dithiophosphonates Phosphoramidates
the most important are malathion, parathion and tetraethylpyrophosphate (TEPP)
Insecticides

P
OR1
R2 X
NO2O
P
C2H5O
C2H5C
Se.g. Parathion
Basic structure
Phosphorganic or Organophosphoric Cs
Insecticides

Phosphorganic or Organophosphoric Cs
Action MechanismThey inhibit Acetylcholinesterase (AChE) in the cholinergic synapses of the CNS they bind to the enzyme active site as competitive substratesof acetylcholine
They inhibit Non-specific Carboxylesterase, called Neuropathy Target Esterase (NTE)
Insecticides

Phosphorganic or Organophosphoric CsFirst step (phosphorylation):
the organophosphoric can be detached from the enzyme
Second step:phosphorylation becomes irreversible ("ageing")
Insecticides

Phosphorganic or Organophosphoric Cs
There are two cholinesterases in the human body: Acetylcholinesterase (also called true or red blood cell
cholinesterase) is specific for acetylcholine and is found in:- erythrocytes, nervous system, neuromuscular junctions, suprarenal glands
Pseudocholinesterase (or plasma cholinesterase) is not specific for acetylcholine and also hydrolyses other substrates. It is found in:
- plasma, myocardium, smooth muscle, intestinal mucosa, skin
Insecticides

Phosphorganic or Organophosphoric Cs
Acute exposure to high doses
Acute Cholinergic Crisis “Intermediate Syndrome” Delayed Polyneuropathy
Insecticides

Phosphorganic or Organophosphoric Cs
Acute Cholinergic Crisis “Muscarinic” symptoms (arising from stimulation of the muscarinic receptors of the parasympathetic postganglionic neurons)
“Nicotinic” symptoms (arising from stimulation of the nicotinic receptors of the sympathetic and parasympathetic ganglia and of the neuromuscular junctions)
Neuro-behavioural effects (arising from stimulation of the nicotinic receptors of the Central nervous System)
Insecticides

MUSCARINIC SYMPTOMS:Respiratory apparatus (bronchospasm, increased secretions, cough, cyanosis, pulmonary edema)\Gastroenteric apparatus (nausea, vomiting, abdominal pain, diarrhea, tenesmus, faecal incontinence\Cardiocirculatory apparatus (arterial hypotension, bradicardia, cardiac arrest)\Urinary apparatus (pollakiuria and incontinence\Visual aparatus (miosis, anisocoria, diplopy)\Exocrine glands (increase in salivation, perspiration and lacrimation)\Locomotor apparatus (muscular asthenia, involuntary tremors, fasciculations and muscular cramps\Cardiocirculatory apparatus (tachicardia, arterial hypertension)
NICOTINIC SYMPTOMS:Metabolism (hyperglicemia)\Skin (intense pallor)
CNS: excitement followed by depression and coma
Insecticides

Phosphorganic or Organophosphoric Cs
“Intermediate Syndrome” It develops 24-96 hours after the acute cholinergic
crisis
It is characterised by myastenia of the neck flexor muscles and limb proximal muscles, and by paralysis of the cranial nerves
High risk of death due to severe respiratory depression, which requires respiratory assistance and shows no response either to atropine or to oximes
Insecticides

Phosphorganic or Organophosphoric Cs
Delayed Polyneuropathy
Sensory-motor distal axonopathy developing 2-5 weeks after acute cholinergic crisis
Initial myasthenia of the upper and lower limbs distal muscles
It is followed by spasticity, hypertonia and hyperreflexia of the these muscles
Insecticides

Phosphorganic or Organophosphoric Cs
Prolonged exposure to low doses Neurotoxicity (Alzheimer's Disease, Parkinson's Disease, etc.) “Endocrine disruption” (reduced fertility, inhibition of GH incretion, increased
melatonine incretion, etc.) Carcinogenity (Non-Hodgkin Lymphoma , Leukemias, Sarcomas, etc.)
Insecticides

Phosphorganic or Organophosphoric Cs
Treatment
Atropine to counter muscarinic effects
Oximes to counter nicotinic and CNS effects
Benzodiazepines to control anxiety and toxicity on the CNS and
neuromuscular system, which are resistant to atropine
Insecticides

Phosphorganic or Organophosphoric Cs
Biological MonitoringErythrocyte cholinesterase activity Advantages: they are highly sensitive indices of exposure, becausethey can be detected in urine at very low exposure levels Limitations: high interindividual variability (pre-exposure values arenecessary for comparison with post-exposure data)
Alkylphosphates in urineAdvantages: they are highly sensitive indices of exposure, becausethey can be detected in urine at very low exposure levels. Limitations: little is known about the relationship between dose andurine levels; aspecificity
Paranitrophenol in end-shift urineLimitations: aspecific
Insecticides

Phosphorganic or Organophosphoric Cs
Exposure limit values
BEI proposed by ACGIH:
A 70% reduction in erythrocyte cholinesterase activity with respect to basal value
Paranitrophenol in end-shift urine for parathion: 0.5 mg/g creatinine
Insecticides

Organic-nitrogen Cs: carbamatesEsters of carbamic acid:
Aromatic Esters Bendiocarb Carbaryl Carbofuran Carbosulfan Pirimicarb Propoxur
Oximes Aldicarb Methomyl
Urea derivatives Diflubenzuron Triflumuron
Triazines cyromazine
Insecticides

NR2 C
R1
O
O
R3
R2 and R3 groups can be an organic radical or simply a hydrogen atom. Group R3 usually consists of an aromatic ring, sometimes linked to a tertiary amine
Basic structure
O C
O
NH
CH3
es. carbaryl
Organic-nitrogen Cs: carbamates
Insecticides

Organic-nitrogen Cs: carbamates
Action Mechanism
They inhibit Acetylcholinesterase (AChE) in the cholinergic synapses of the CNS. Unlike with organophosphates, inhibition is reversible and short-lived
Insecticides

Organic-nitrogen Cs: carbamates
Acute exposure to high doses
Symptoms (acute cholinergic crisis and
“intermediate syndrome”) can bedistinguished from those of organophosphatesintoxication by their:
Shorter duration Lower intensity Lack of delayed polyneuropathy
Insecticides

Organic-nitrogen Cs: carbamates
Prolonged exposure to low doses
Neurotoxicity (Alzheimer's Disease, Parkinson's Disease, etc.)
“Endocrine disruption” (reduced fertility, inhibition of FT3 and FT4 incretion, etc.)
Carcinogenity (Non-Hodgkin Lymphoma, Leukemias, Sarcomas, etc.)
Insecticides

Organic-nitrogen Cs: carbamates
Treatment Atropine to counter muscarinic effects
Benzodiazepines to control anxiety and toxicity on the CNS and neuromuscular system, which are resistant to atropine
No Oximes, because they do not interact with carbamylated acetylcholinesterase
Insecticides

Organic-nitrogen Cs: carbamates
Biological Monitoring Hematic cholinesterase activity: monitoring of pre/post-exposure erythrocyte AchE levels (within 4 hours from exposure)
The urinary metabolites of some carbamates are known:
1-urinary naphtol for carbaryl 3-hydroxicarbofuran in urine for carbofuran 2-isopropoxyphenol for propoxur
However, we have no BEI values (the relationship between exposure and urinary levels is unknown)
Insecticides

Chloro-organic or organochlorinated Cs They are chlorinated hydrocarbons belonging to
three distinct chemical classes:
Dichlorodiphenylethanes Cyclodienes Hexachlorocyclohexanes and chlorinated benzenes
They were introduced in the forties, both in the agricultural sector and against insects vectoring infectious diseases
Compounds with exceptional chemical stability and high lipophilia, accumulating in the environment and biological systems
Insecticides

Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Cl
Chloro-organic or organochlorinated CsHeterogeneous group of compounds, sharing insecticidal properties and the presence of chlorine atoms
Cl Cl
C(CCl)2
DICHLORODIPHENYLETHANES(DDT, Dicofol, Metolachlor…)
Cyclodienes(Aldrin, Heptaclor, Endosulphane…)
CHLORINATED BENZENES CYCLOHEXANES
1
2
3
Insecticides

Chloro-organic or organochlorinated Cs
Action mechanism
For dichlorodiphenylethanes, four mechanismshave been proposed, which mainly affect the
sensitivenervous fibres of the PNS:
• Reduction of potassium transport• Inactivation of sodium channels• Inhibition of sodium-potassium and calcium-magnesium
ATPases• Interaction with calcium/calmodulin and neurotransmitter
release
Reduction in the velocity of neuronal membrane repolarization
Insecticides

Chloro-organic or organochlorinated Cs
Action mechanism
For cyclodienes, cyclohexanes and chlorinatedbenzenes, two mechanisms have been hypothesised,which mainly occur in the CNS:• Antagonism of the GABA neurotransmitter by blockage of
chlorine channels• Inhibition of Ca2+, Mg2+-ATPase, with cumulation of intercellular
free calcium and increase in calcium-dependent release of neurotransmitters from the vesicles
Reduction in the velocity of neuronal membrane repolarization
Insecticides

Chloro-organic or organochlorinated Cs
Acute exposure to high doses
Paresthesias (especially facial paresthesias) Hypersensitivity to external stimuli Irritability Tremors (“Kepone shakes”) Tonico-clonic convulsions
Insecticides

Chloro-organic or organochlorinated Cs
Prolonged exposure to low doses
Neurotoxicity (Parkinson's Disease) “Endocrine disruption” (estrogenic and antithyroid action) Carcinogenity (leukemia, Non-Hodgkin lymphoma, soft tissues
sarcoma, hepatic and breast tumours )
Insecticides

Chloro-organic or organochlorinated Cs
Treatment
DecontaminationSupport treatmentDiazepam or phenobarbital (for convulsions)Cholestyramine (it reduces enterohepatic
circulation)
Insecticides

Weed killers or Herbicides
Classification
Chlorophenoxy compounds: MCPA (4-chloro-2-methylphenoxyacetic-acid) 2,4 D (2,4 dichlorophenoxyacetic acid) 2,4,5 T (2,4,5 trichlorophenoxy acetic acid)
Bipyridyl compounds: Paraquat Diquat
Triazines: Atrazine Simazine Propazine

2,4,5 T (2,4,5 trichlorophenoxy acetic acid)
Action mechanism mediated by the TCDD contamination
(2,3,7,8,tetrachlorodibenzo-p-dioxin or dioxin), it arises from the synthesis of these compounds when temperature is not strictly controlled
dioxin is teratogenic and carcinogenic to humans
It also causes a severe contact dermatitis called “chemical workers chloracne”
Weed killers or Herbicides

2,4,5 T (2,4,5 trichlorophenoxy acetic acid)
Acute exposure to high doses
vomiting myalgia headache asthenia chloracne
Weed killers or Herbicides

2,4,5 T (2,4,5 trichlorophenoxy acetic acid)
Prolonged exposure to low doses
Neurotoxicity (Lateral Amyotrophic Sclerosis)
“Endocrine disruption” (reduced fertility)
Carcinogenity (Non-Hodgkin lymphoma, soft tissue sarcoma, prostatic carcinoma)
Weed killers or Herbicides

Paraquat
Action mechanisms
Formation of free radicals and peroxydation at the:
Pulmonary (alveolar) level Hepatic level Renal level
Fibrosis Organ failure
Weed killers or Herbicides

Paraquat
Acute exposure to high doses
Signs and symptoms of acute ventilatory failure
Signs and symptoms of acute renal failure
Signs and symptoms of acute toxic hepatopathy
Weed killers or Herbicides

Paraquat
Prolonged exposure to low doses
Neurotoxicity (Parkinson's Disease) No evidence of “Endocrine disruption”
No evidence of Carcinogenity
Weed killers or Herbicides

Occupational MedicineProf. Francesco S. Violante
Occupational Tumours

Tumours are defined as “occupational” when work-related exposure to carcinogenic agents acted as a cause or joint-cause in their genesis
Occupational Tumours

Occupational Tumours
GENERAL CHARACTERISTICS
Target organs Latent period Dose-response relationship Histological type IARC lists Primary sites

TARGET ORGANS
Occupational tumours arise: at the site of carcinogenic contact: Direct carcinogens At the target sites of the carcinogen: Indirect carcinogens
Target organs can be:- entry routes (e.g. skin, bronchial epithelium)- metabolic sites (e.g. liver) - accumulation sites (e.g. Hemopoietic marrow)- routes of elimination of active metabolites (e.g. Urinary pathways)
Occupational Tumours

Latent Period
The time elapsing between the beginning of carcinogen exposure and the clinical appearance of the tumour

Dose-response relationship
It is not known whether threshold levels exist, below which no increase in tumours occurs

Histological Type
From a histological point of view, occupational tumours cannot be distinguished from “spontaneous” neoplasia occurring at the same site.

International Agency for Research on
Cancer (IARC)
Chemical substances or mixtures of substances that induce occupational tumours and related target organs
Industrial processes responsible for occupational tumours and related target organs
Occupational Tumours

Primary Sites of Occupational Tumours
Skin Respiratory tract Lung Mesothelia (serous membranes) Urinary tract Hemopoietic marrow Liver

Skin and Occupational Tumours
Occupational cutaneous tumours are carcinomas induced by: Chemical agents(e.g. IPA, unrefined mineral oils, arsenic compounds) Physical agents(e.g. Ionizing radiations and UV rays)

Respiratory Tract and Occupational Tumours
Carcinomas of the nasal and paranasal cavities: Nickel compounds, wood dusts (especially from hard woods), Chrome compounds VI
Nasopharynx carcinomas: formaldehyde

Lung and Occupational Tumours
Main causal agents IPA Asbestos Crystalline silica (?) Radon bis(chromomethyl)ether (BCME) As compounds Ni compounds CrVI compounds
Be compounds

Mesothelia and Occupational Tumours
Characteristics of mesotheliomas
Most affected serosa: pleura Latent period: 10-40 years Dose-response relationship: absent Causale agent: asbestos

Urinary Tract and Occupational Tumours
Main causal agents
IPA Aromatic amines Benzidine: production and use of azo colourings 4-aminodiphenyl: only produced in the USA 2-naphthylamine: production and use of azo colourings
production and distillation of gases from coal 0-toluidine: production of 4-chloro-toluidine 4-chloro-toluidine: production of chlordimeform

Hemopoietic System and Occupational Tumours
Main leukemogenic agents
Benzene 1,3-butadiene (group 2A, IARC) Ionizing radiations Ethylene oxide (group 1, IARC)

Liver and Occupational Tumours
Hepatic angiosarcoma
The liver is the main target organ of vinyl chloride monomer (VCM), which induces various types of tumour, in particular angiosarcoma

Conclusions
It is important to identify biomarkers of
exposure to genotoxicants and/or early
biological effects of genotoxicants

Occupational MedicineProf. Francesco S. Violante
Occupational Infections

D. L.vo 626/94 and further modificationsTitolo VIII: Protection against biological agents
Field of application (art. 73)
Any work activity involving risk of exposure to biological agents(excluding genetically modified microorganisms (GMMOs), whose use is regulated by D. L.vo 206/01.)
Regulations

Regulations
Annexes to D. L.vo 626/94 and further modifications
Annex IX: Illustrative list of work activities, which can involve the presence of chemical agents
Annex X: Index of biological risk Annex XI: List of classified biological agents Annex XII: Specifications on control measures and
levels Annex XIII: Specifications for industrial processes

Annex IX: List of work activities, which can involve the presence of chemical agents
Food industries Agriculture Contact with animals and/or animal products Sanitary services, including isolation and post- mortem units Clinical, veterinary and diagnostic laboratories, excluding microbiological diagnosis Potentially infected plants for waste disposal and special waste collection Plants for purifying drain waters
Regulations

MINISTRY OF HEALTH:Chemical Agents, Category A (high priority)
Microbiological characteristics (definition, possible diffusion media, environmental resistance, sources of contagion, methods for the decontamination and disposal of contaminated materials, transport of biological samples)
Epidemiological/clinical characteristics (transmission pathways, duration of incubation and
contagiousness, clinical characteristics, control methods, diagnostics, precautions for the patient, transportation and evacuation of patients, measures for exposed persons, contacts and assistance personnel, treatment)
Regulations

Employer's Obligations:
Risk assessment document (RAD)
Technical, organizational, procedural and hygienic measures
Information and trainingSanitary Surveillance – prevention and
control
Regulations

Workers whose risk assessment evidenced an health risk are submitted to sanitary surveillance.
Upon advice of the occupational physician, the employer adopts special protection measures:
• Effective vaccines• Temporary removal\ascertainments\ RAD revision• He provides information on the sanitary controls they are
submitted to, on the necessity to undergo sanitary checks, even after the end of the activity, and on the disadvantages of vaccination
Regulations

DELIBERATE OR POTENTIAL BIOLOGICAL RISK
Deliberate risk: Biological agents are deliberately introduced into the working cycle either for treatment, manipulation and transformation or to exploit their biological properties
University and research centres, Public Health, Zootechnics and Veterinary practice, Biotechnology and Farmaceutical industry, Food industry, Chemical industry, Energy industry, Environment, Mines, Agriculture, War industry

Potential risk:The presence of chemical agents not intended for a specific use
Food industries, Agriculture, Zootechnics, Meat slaughtering and processing, Veterinary services, Sanitary services, Diagnostic laboratories, Waste collection, processing, and disposal services , Disinfection and disinfestation service, Rain water purification plants
DELIBERATE OR POTENTIAL BIOLOGICAL RISK

RAD: deliberate risk Gathering information on the microorganism
(infectivity, pathogenicity, etc.) and its related pathologies, epidemiology, mode, volume and frequency of manipulation
Evaluation of diffusion and future in the environment (control measures, assessment of CPDs, environmental monitoring, etc.)
Risk characterisation (incidence and severity of human health damage and environmental impact)
Risk management (training/information, CPD, IPD)
Reduction of risk to an acceptable level
DELIBERATE OR POTENTIAL BIOLOGICAL RISK

RAD: potential risk
Biological agents can induce:Infections caused by parasites, viruses and
bacteriaAllergies caused by exposure to moulds,
yeasts, and organic dusts (e.g.: flour dusts, acari)
Poisonings or toxicogenic effects
DELIBERATE OR POTENTIAL BIOLOGICAL RISK

CONTAMINATION SOURCES
External airConditioning systemsPresence either of diseased individuals or
healthy carriersFoodstuffsAnimals
Biological dusts: allergic respiratory diseasesFungi Aspergillus \ Alternarium \ Penicillium Streptomyces albus Bacteria Bacillus subtilis \ Bacillus Cereus\ Euroglyhus\Staphylococcus aureus\Strespococcus pyogenes\ Pseudomonas aeruginosa\Legionella Acari Acarus Dermatophagoides
BIOLOGICAL RISK

FOOD INDUSTRYFood sector
(production of foods and food additives)
ALLERGIESMoulds\ yeasts, bacteria, acari\ Organic dusts\ Powdered milk or flour contaminated by biological agents\ Toxins (e.g.: botulinum toxins, aflatoxins)
FOOD TOXINFECTIONSSalmonella typhi\ Staphylococcus aureus\ Escherichia
coli\Listeria monocytogenes\Clostridium botulinum\Vobrio
cholerae\Hepatic virus A\Gastroenteric viruses
BIOLOGICAL RISK

AGRICULTUREagricultural, forest, horticultural sector and production of animal feedstuff
Traumas: infections caused by pyogenes, vibriones, hookworm larvae, clostridia (tetanus and gas gangrene), anthrax Sewage and water distribution: enterovirus, coli, salmonellae, vibrio cholerae Vectors (cockroaches, rats, ticks): leptospirosis, salmonellae, enterobacteriaceae, coliforms, Lyme disease and Q feverWild animals (foxes, dogs, ferrets, weasels): Rhabdovirus
Respiratory disorders caused by microorganisms/acari in cereal dusts, powdered milk, flours and spices (ODTS – Organic Dust Toxic Syndrome) Specific allergic disorders (“Farmer's lung” or “Bird breeder's lung” due to chronic exposure)
BIOLOGICAL RISK

RISKS ASSOCIATED WITH ZOOTECHNICS Harmful gases and vapours associated with
unpleasant odours (organic compounds with either N and/or S or H2S, NH3) Bacterial or viral infections due to contact
with sewage (bacteria, viruses, eggs of intestinal worms, parasitic fungi) and to inhalation of contaminated aerosol (e.g.: feedstuff contaminated by moulds or
mycetes disorders of the respiratory system or contaminated by BSE prions?)
Vectors carrying pathogenic germs (ticks, rats, cockroaches)
Pollution in shallow and deep waters Diseases transmitted by animals (ZOONOSES)
BIOLOGICAL RISK

Zoonoses: diseases transmitted by animals to humans and vice versa. They affect breeders and those who have occasional contact with breeding animals (veterinary doctors, animals traders and transporters, slaughterhouse operators, operators of the animal by-products sector)
Zoonoses in bovine breedingBrucella abortus (brucellosis), Mycobacteria (tuberculosis),
Clostridium tetani (tetanus), Coxiella burnetii (Q fever), mycetes (mycosis)
Zoonoses in swine breedingBrucella suis (brucellosis), Leptospira SPP (leptospirosis), Erysipelothrix
Rhusiopathia (erysipelas), Clostridium tetani (tetanus), mycobacteria
(tuberculosis), Streptococcus suis (streptococcosis)
Zoonoses in the slaughtering sector:brucellosis and TBC (cattle); leptospirosis and erysipelas
(swine)
BIOLOGICAL RISK

Scabies,Ringworm
Rabies,Tetanus
Leptospirosis
Salmonellosis, Hydatidosis, Cutaneous Larva migrans , Visceral Larva Migrans
contact
Bite and scratchesurine
feci
Leptospirosis
Toxoplasmosis
Psittacosis
Scabies, Ringworm
Rabies, cat scratch disease
BIOLOGICAL RISK
zoonoses

HEALTH SECTOR RISKSHospitals , outpatient clinics, dentist surgeries, assistance services Bacterial and viral infections: HIV, viral hepatitis (B\C), tuberculosis, salmonellosis, legionellosis Most frequent accidents: slashes and punctures, contact with biological fluids
RISKS IN DIAGNOSTIC LABORATORIES (excluding microbiology laboratories) Infections and allergies due to the manipulation of m.o. and cell cultures (e.g. Human tissue cells) Most frequent accidents: accidental leakages, needle and glassware injuries
BIOLOGICAL RISK

RISKS IN THE CONSTRUCTION INDUSTRY Moulds and bacteria originating from decay of construction materials Clostridium tetani, leptospires, coliforms, enterobacteriaceae, amoebas, acari, helminths carried by insects or rats or residing in non-hygienic environments
RISKS ASSOCIATED WITH WORK IN ARCHIVES, MUSEUMS AND BOOKSHOPS Moulds/yeasts and bacteria causing allergies and respiratory disorders
BIOLOGICAL RISK

RISKS ASSOCIATED WITH SEWAGETREATMENT
Formation of contaminated aerosolSalmonellae, Vibrio, escherichia, poliovirus, adenovirus, eggs of intestinal parasitesSewage worker’s Syndrome
RISKS ASSOCIATED WITH WASTE DISPOSALRisks vary according to waste type (hospital waste, sewage, etc.)Waste recycling and composting plants: allergic phenomena and respiratory disorders due to the presence of moulds (aspergillosis)
BIOLOGICAL RISK

TRADIZIONAL P.
Fermentative techniques
Modern techniques
AVANZATE Designed biological systems
RISKS ASSOCIATED WITH BIOTECHNOLOGICAL PROCESSES
BIOLOGICAL RISK

RISKS ASSOCIATED WITH
BIOTECHNOLOGICAL PROCESSES Immunopathies: allergies (bronchial asthma and
contact dermatitis – irritative or allergic dermatitis) Toxic effects: e.g. hypovitaminosis, disbacteriosis,
virulence of flora (production of antibiotics and hormones) or reproductive disorders in women working in the production of progestogenic substances
Pathogenic effects: induced by artificially manipulated organisms and vectors like phages, retroviruses, plasmids, etc.
BIOLOGICAL RISK

RISK ASSESSMENT: SAMPLINGS AND ANALYSIS
Each microorganism can be defined by an INFECTING DOSE (DI50) typical of each species
In order to distinguish between presumed and actual risk, risk assessment should include a MINIMUM INFECTING DOSE (DI50) or INFECTIVITY THRESHOLD
The INFECTIVITY THRESHOLD of several microorganisms is close to unity (DI0=1), but in case of high pathogenicity and transmissibility, and low neutralizability, exposure should be eliminated

Risk Estimate
Identifying the production phases in which exposure can occur Attributing a priori preventive and protection measures on the basis of scientific knowledge A posteriori identification of potential contamination sources
A series of control measures and optimized procedures will be developed for each critical phase of the working cycle Setting-up of analytical environmental monitoring or systematic inspections
RISK ASSESSMENT: SAMPLINGS AND ANALYSIS

Environmental Monitoring
BIOAEROSOL = aerodispersed biological particles
Fungal spores
Pollen
Viruses, bacteria, yeasts
Algae and protozoa
Insect fragments or insect excrements
Skin flakes or mammal hairs
Residues or products of organisms like (endotoxic or mycotoxic) bacterial lipopolysaccharides

Estimation of biological contamination
Expression of results Colony-forming unit (CFU/m3) per vital organisms Number of cells, spores or pollen grains, in case vitality is
undetermined Chemical determinations (ng, mg/m3) in the presence of
endotoxins.
TYPE MEDIUM SIZE (mm)
Viruses 0.02 – 0.3
Bacteria 0.5 – 10
Endospores 0.5 – 3
Fungal spores 1 – 100
Pollen 10 - 100
Environmental Monitoring

Estimation of biological contamination
Bioaerosol analysisCalculation of coloniesATP – bioluminescenceChemiluminescenceFluorescence microscopy Phase contrast MicroscopyImmunological tests
Air Microbial Index (AMI) for surgery rooms and intensive care units:
normal: germs in air from 0 to 15/m3\ uncertain: from 16 to 75/m3\ altered: > 75/m3
Environmental Monitoring

EVALUATION OF CONTAMINATION
Contamination of surfaces Verifying the effectiveness of the decontamination
system which is being used Controlling the correspondence between actual
aseptic level and the level of asepsis required for a specific process
Verifying the absence of biological dispersions out of containment areas
Types of surface monitoring
A case/control - Upstream/downstream – Longitudinal analyses of temporal series
Environmental Monitoring

Biological Risk Prevention
CONTAMINATION
Direct or indirect contact with an infection source or reservoir Collection, handling or transport of infected biological material (faeces, urine, blood, etc.) and other infected materials (needles, syringes, scalpels, etc.) Genetic engineering practices involving the use of microorganisms or their parts

MAIN TRANSMISSION ROUTES
contact: direct or indirect contactaereal route: extremely small microorganisms
contained in droplets (small respiratory drops expelled from an infected reservoir through coughs, sneezes, singing, etc.)
parenteral route: inoculation or contact of mucosae and injured skin with blood, blood products or other biological material
Biological Risk Prevention

INFECTION ROUTESVie di penetrazione
Esempi di agenti biologici (classe di rischio)
Protezione dell’operatore
Bocca (ingestione) Salmonella (2), Shigella (2), Clostridium difficile (2), Virus epatite A (2)
• è viet at o aspirare dalla pipet t a con la bocca
• è viet at o m angiare e fum are in laborat orio
• evit are di port are alla bocca qualsiasi ogget t o u t ilizzat o nel laborat orio
Narici ( in alazion e) Mycobact erium t ubercolosis (3), Legionella Pneum ophila (2), Brucella (3), Virus respirat orio sinciziale 2), Cyt om egalovirus (2), St rept ococcus pneum onit e (2)
• evit are di sorvegliare operazion i crit iche com e la sem ina ed l’apert ura delle piast re e delle provet t e, la cent rifugazione, l’om ogenizzazione senza indossare i DPI (disposit ivi di prot ezione individuale)
Pelle ( in iezion e) Virus Epat it e B (3* * ) e C (3* * ), HI V (3* * ) Herpes Sim plex (2), Candida Albicans (2)
• m aneggiare con m olt a at t enzione aghi, pipet t e Past eur, vet reria rot t a
• prot eggere accurat am ent e t agli, ferit e o abrasion i present i su lla pelle
Occh i ( sch izzi) Herpes sim plex (2) • prot eggere sem pre gli occhi • non ut ilizzare lent i a cont at t o
Biological Risk Prevention

PREVENTION MEASURES
Increasing host resistance (active or passive immunization through vaccines and immunoglobulins)
Inactivating the infective agent (cleansing, disinfection and sterilizing by use of chemical or physical methods)
Interrupting the infection chain (treatment of sanitary materials, waste collection and disposal, standard precautions)
Biological Risk Prevention

PREVENTION INTERVENTIONS
Environmental intervention Verifying the proper functioning of containment areas Disinfection (formaldehyde, UV, etc) Disinfestation Appropriate air filtration systems Waste and sewage treatment
Individual Intervention Use of IPD Washing and disinfection systems
Biological Risk Prevention

SAFETY MEASURES
Work organization Training - information Containment measures Access control, safety signs
Biological Risk Prevention

GENERAL PRECAUTIONS
Any biological sample should be treated as potentially dangerous:
Use of IPDKeeping hands away from face and washing
hands frequentlyDo not eat, drink, or smokeDo not wear make-up/contact lenses
Biological Risk Prevention

Reducing the use of needles and cutting objects and avoid recapping syringes after use
Decontamination of worktops using effective chemical disinfectants
Mouth pipetting is forbidded; mechanical pipetting devices should be used instead (automatic pipetters) or pipettes with filtered tips
Keeping laboratory clean and tidy
Biological Risk Prevention

PRECAUTIONS IN HANDLING AND TRANSPORTAT OF BIOLOGICAL SAMPLES
Potentially infected materials should be handled so as to avoid any dispersion
Biological Risk Prevention

INDIVIDUAL PROTECTION DEVICES (IPD)
Face protectionsurgical masks\breathers
Body protectionwaterproofs gowns\jackets
Gloveslatex, vinyl, nitrile sterile gloves
Eye protectionsafety glasses\screens
Biological Risk Prevention

EMERGENCY MEASUREMENT
D. Lvo 626/94 – Art. 84 Emergency measures
Qualora si verifichino degli incidenti con A. B. di classe 2, 3 o 4 i lavoratori devono immediatamente lasciare la zona interessata, cui possono accedere solo gli addetti ai necessari interventi, con l’obbligo di indossare i DPI
Il DdL informa al più presto l’organo di vigilanza territorialmente competente nonché i lavoratori, gli RLS delle evento, della cause che lo hanno determinato e delle misure che si sono o si intende adottare
I lavoratori segnalano immediatamente al DdL o al dirigente o al preposto qualsiasi infortunio o incidente relativo all’uso di A.B
Biological Risk Prevention