This report is about an industrial site that has been used for discarding wastes by two companies. The companies have been operating for a period close to sixty years. The site is situated on the upper side of a residential area and separated by an approximate distance of one mile.
Running through the site is a stream that serves the community in some ways. First, the stream is an as it is a prominent fishing ground.
There is an underground water withdrawal point at the site that is used to bring in water to the residents. The villagers pump water from the stream to their nearby farms for irrigation.
There are however, few environmental negative aspects noted at the waste site. Approaching the site, a strong pungent smell from chemicals released by the two companies hits the air. A critical evaluation of the site reveals that there one hundred drums that unfortunately are not marked.
The drums are rusting and most of them have cracked. Further evaluation leads to the finding of various hazardous wastes that include PCBs, Chromium wastes, Acrylamide and Toluene Diisocynate (DTI).
This report was written after a visit to the site and it seeks to analyze the environmental conditions at the site, find the toxicants, their routes of exposure along with the mechanisms of toxicity.
The report makes recommendations on the actions that should be taken to avert an epidemic and other toxicological effects that could be caused by toxicants. This is after an analysis of the exposure limits of the toxicants and the assessment of the risks at the site.
The hazardous wastes found at site are industrial products discarded by the companies and by-products of the manufacturing processes. The wastes are a mixture of solids, gases, sludge, and liquids. The wastes are dangerous and harmful to the environment and human health.
These are the Polychlorinated Biphenyl (PCB) wastes. They are compounds of hydrocarbons and are mainly synthetic (Deng, 1990). Their level of toxicity varies and widely ranges depending on their color i.e. whether they are yellow, black, waxy solids or if they are light-colored liquids.
They are common in industries because they are the main components of insulators. Industrial products that contain PCBs include most electrical equipment such as capacitors, electromagnets, voltage regulators, transformers, and reclosers.
Cable insulators and other materials that make thermal insulators such as foam, fiberglass, and felt also have PCB.
The PCBs at the site are exposed to the environment during the manufacturing processes. This is in addition to the poor mechanisms of dumping wastes used by the companies. The maintenance of the site is poor. This increases the exposure levels making the wastes more hazardous.
Keen observation of the site also revealed that there were leaches streaming into the site. This could only mean that the companies have some of their poorly maintained.
PCBs do not rot. They create a cycle around the soil, air, and water for many years. They are carried as loads and moved to far of distances if found in water Just like other toxicants, PCBs have bioaccumulative effects. This is mainly in animals and crops used for human consumption.
At the site fish from the stream and the irrigated crops have huge amounts of the toxicant. The toxicological effects of PCBs are many and varied (Flora, 1987). A part from causing cancer, they impair the nervous system, endocrine system, and the reproductive system.
Research by health practitioners confirms that PCBs have both carcinogenic and non-carcinogenic effects. The most common PCB mixture associated with cancer is bioaccumulative in fish. Residents therefore, feed on fish that is exposed to PCB. They are at a greater risk than the workers in the two companies are.
Exposure to PCB cuts the power of the body to respond to environmental stimulants. It also decreases the power of the body to . PCB is likely to cut the size of thymus gland.
From the reproductive front, they cut the weight of the offspring at birth, men can also experience low sperm count and a shorter gestation age in women. The manufacture of PCBs was however, banned in 1979 and the government does not allow any exposure limits.
The second hazardous waste discovered at the site was chromium waste. Chromium is a steel metal that is hard and gray in color.
The industries using the site as a waste site have for more than sixty years used Chromium in the manufacture of Stainless steel and as a component of other alloys of metals because it does not rust even at high temperatures. The companies also use it in getting average paint pigments be it yellow, green, or even red (Gosselin, 1984).
It is also used in the treatment of wood along with making chrome plates. In small amounts, the companies use it in catalysts, water treatment, and photographic chemicals. Chromium is useful to the human body as it strengthens insulin and eases the metabolism of glucose and other sugars.
The companies release Hexavalent Chromium and other Chromium wastes to the site. The wastes have carcinogenic effects. The exposure of Chromium wastes to the environment usually contaminates the air. Combustion activities within the two companies led squarely to this.
Elements of Chromium wastes react with dust particles from the environment to form very toxic substances with the potential to damage the health of residents. The leaches from waste storage tanks that are poorly maintained by the company directly mixes with water in the stream.
The solids wastes are discarded improperly at the site and they contaminate stream water used for fishing and irrigation. The leaching waste contaminates drinking water in the area.
Further exposure of Chromium waste to people near the site comes from the waste slag. This is inhaled as it comes by wind erosion. They also consume fish that is exposed and through skin contact with soils as they use the steam water during irrigation.
The environment in this area and its vicinity provides the largest exposure source to Chromium wastes. This includes chemical effluents, airborne emissions, and asbestos linings.
In general, it could be said that Chromium gets into the human body through consumption of fish, inhalation of emissions from the companies and skin absorption during irrigation. The regulations guiding Chromium by the government are meant to protect the public from its unpleasant effects.
The government through the Occupational Safety and Health Administration (OSHA) restricts to a maximum of eight hours exposure limits to five micrograms of Chromium per cubic meter of air. This cuts down the industrial risk to health impairment.
The risks include developing asthma and damaging both the skin and nasal epithelia. The Environmental Protection Agency (EPA) has regulated the amount of Chromium emissions into the air from 1990 to date.
Acrylamide has carcinogenic effects and is a reproductive toxin. Its components are found in liquid form at the site and in the stream. It is highly toxic in this form as it can be inhaled; absorbed through the skin as residents work on their farms using contaminated water and consumed when the residents feed on fish.
The companies use Acrylamide in the manufacture of plastic polymers in addition to synthesizing dyes and construction of tunnels that serve to dispose their by-products to the dumping site.
The exposure of Acrylamide is largely through wastes as the companies use it in sieving industrial wastes to remove solids (Manahan, 1990). In the end, they discard it with water. Acrylamide has a vapour density of 2.5 and very soluble in water.
It contaminates the stream interfering with the living environment for fish. This complements its almost colorless nature. Following the unprotected way it is disposed, its effects tend to be very adverse.
From the analysis of the site, it is clear that the two companies emit TDI. Its toxicological effect is high, as it does not dissolve in water. The main route of exposure of Toluene is through inhalation.
Small amounts of TDI cause irritation to the lungs and the respiratory tract. OSHA allows its exposure levels to a maximum of 0.02 ppm yet people close to factories can inhale as much as 2.1 ppm. This is one hundred times more than the exposure limits.
Workers in the two companies are at the risk of contacting asphyxiation if their rooms are poorly ventilated. Children in the residential areas are at the receiving end of TDI too. The risks increase because of the economic activities in the area i.e. fishing and irrigation.
Contact with the skin causes irritation and may result in inflammation of the mucous membrane. NIOSH IDLH puts the exposure limits of TDI to a scale of 2.5 ppm as an immediate danger to health and life (Toxic, 2000).
An analysis of the above conditions clearly explains that the environment and the residents near the site are at risk. The toxicological effects of the available toxicants are bioaccumulative.
The outbreak of other diseases is eminent and therefore the government ought to take the initiative to avert a looming health crisis. Men, women, and children may contact diseases some of which are contagious.
Based on the research conducted at the site, it is highly recommended that the government health departments put protective measures in place because the residents are exposed to various risks that can cause diseases now and in future.
Other effects could mean that children exposed to the toxicants could develop complications in their late twenties. This report could as well form part of the preliminary research process by the department.
It should move fast and work in collaboration with the two companies and the residents in addressing the hazardous effects of the wastes at the site. This should include taking proper care of the site by first undertaking a thorough cleaning exercise.
This will make sure that fish from the stream is safe for human consumption. Water used for irrigation will also be safe for use, as the mixed chemicals will be removed.
Examining the numerical relationship between the exposure levels and effects of the toxicants it is possible that villagers are exposed to too much toxins.
The government should stop this, as the consequences could be unmanageable. A study should be conducted to show the extent to which the toxicants explained above have affected the environment with corrective measures put in place.