Sources of Oil and Water Pollution- Environmental

Metals and Metalloids

8.1: Oil pollution 8.2: Water pollution 8.3: Environmental metals and

metalloids 8.4: Lead (Pb) 8.5: Cadmium (Cd) 8.6: Mercury (Hg) 8.7: Nickel (Ni) 8.8: Arsenic (As)

Oil and petroleum are ever-present pollutants in the modern environment

Sources: accidental spills from ships, pipelines, leaks in storage tanks and used oil of private motorists.

In oil pollution, there is oil-in-water and water-in-oil

Oil Pollution

Oil-in-water not only at surface but throughout the body of water as well. It can sink to the bottom

Water-in-oil is a spread on the surface and what is commonly seen lying on the surface of the water.

Oil slicks are the main cause of birds deaths.

Exxon Valdez is the most popular case of oil pollution

Occurs when some substance degrades a body of water to such a degree that water cannot be used for a specific purpose.

Water pollution

Types of water pollutants: Point source- discharge of

pollutants from single point (factories, industrial outfall, power plants)

Non-point source- sources of pollution that are scattered/diffuse (e.g. rainfall, fertilizer runoffs, soil erosion, surface runoff, farm field)

Disease causing agents (pathogens)- bacteria, viruses, protozoa Among the major waterborne diseases

are cholera, typhoid, polio

Oxygen demanding waste- organic wastes decomposed by aerobic bacteria. Oxygen (dissolved oxygen) levels in water decline with activity. Low levels of oxygen causes death to fish, plants and other organisms.

Major pollutants in water

Biochemical oxygen demand (BOD)-measure the amount of oxygen consumed in water by aerobic decomposers.

Heavy metals- Dangerous pollutants and often are deposited in sediment in the bottom of streams and may be incorporated in plants, food crops and animals (persistent pollutant)

Environmental metals are often known as heavy metal which are environmental concern.

There are three types of environmental metals

a. Metals that are suspected carcinogen

b. Metals that move readily in the soil

c. Metals that move through food chain

Environmental metal and metalloid

Carcinogen are the agent that can cause cancer in human

Cancer is usually cause by the genetic substances changed by mutagen. Carcinogen is one example of mutagen.

a. Metals that are suspected

carcinogen

This type of environmental metal enters the soil and water system through soil deposition

Through this deposition, the metals will enter water system and vegetation as well as forest. This will end up being move through food chain.

Metals that move readily in soil

This type of metal is the most concern in environmental as it bring long-term effect to human health and ecosystem.

The metals enters the food chain through water, air and soil pollution and eventually accumulate in organisms tissue e.g. fish, paddy, etc.

c. Metals that move through

food chain

Metalloid is known as an element that having both metal and non-metal properties or semi-metal

Example of metalloids are silicon, arsenic and antimony

Environmental Metalloid

Heavy metal that bring acute health effect to human

Sources of lead are lead pipes, lead join soil contaminated from fallout leaded gasoline, leakage of lead from hazardous-waste sites

Impact of lead consuming: Affect central nervous system

Lead (Pb)

Lead poisoning occur commonly in children, particularly in older house as children may consumed chips of lead contaminated paint.

Toxic effects of lead includes fatigue, sleep disturbance, anemia, colic and neuritis (mild exposure)

Severe exposure- encephalopathy, mental retardation, impaired vision (rosak penglihatan).

This metal can accumulate in tissues of aquatic organism, thus leading in increased concentration of cadmium in food chain.

Cadmium tend to accumulate in kidney and liver.

Sources: industrial, mining

Cadmium (Cd)

Cadmium is also known as a carcinogen as it can cause cancer or tumors in lung, kidney, and prostate (for men)

Cadmium poisoning is more likely to affect battery workers and shelters

The famous case of cadmium poisoning is the itai-itai case in Japan

Itai-itai disease is a combination of severe kidney damage, and painful bone and joint.

Itai-itai also known as painful-painful

This disease has been caused by rice contaminated with high level of cadmium

This is resulting from the soil irrigation with water containing cadmium released from industrial sources.

Itai-itai case in Japan

Mercury is widely used in scientific and electrical apparatus

Most mercury poisoning is caused mainly by eating fishes that are contaminated with mercury.

Sources- industrial waste, mining The most popular case of mercury

poisoning is the Minamata disease in Japan.

Mercury, Hg

In 1950s and 1960s, Minamata Bay in Japan had been contaminated with mercury discharge from wastes of chemical and plastics plant.

These discharge absorbed and accumulate in fish and shellfish. These contaminated organisms are consumed by local population and leads to mercury poisoning.

Minamata disease

There are 107 deaths reported and 800 over cases regarding the Minamata disease.

Pregnant mother which have consumed those contaminated fish and shellfish appeared to be healthy, however their infants developed celebral palsy-like symptom, ane mental deficiency

The symptom of mercury poisoning are:

a. Inflammation of the mouthb. Muscular tremor (shake)c. Physic irritationd. Nephritis syndrome (kidney

related disease)

Exposure to mercury may result in severe damage to the nervous and reproductive systems and may ultimately be fatal

Common symptoms of mercury poisoning are poor coordination and altered sensory perception

Pregnant women and children are especially vulnerable to mercury exposure

The most common cause of mercury poisoning is the consumption of fish contaminated with methymercury.

Extra notes on mercury

Sources of Nickel:a. Combustion of coal and fossil

fuelsb. Steel productionc. Mining and refinery

productiond. Municipal sewage treatment

plant

Health effectsa. Skin allergicb. Lung cancerc. Chronic bronchitisd. Asthma

Nickel (Ni)

Sources: pesticide sprays, combustion of arsenic containing fossil fuels, leaching of mine tailings and smelter runoff.

High level of exposure: abnormal skin pigmentation, hyperkeratosis, nasal congestion, abdominal pain.

Arsenic (As)

Low level of exposure: cancers of skin, lung and lymph gland.