Hazards that Remain after Industrial Sites Are Closed Report

Overview

The site I visited is an industrial waste site that has been abandoned by two companies who have been using the site for the last sixty years. A closer look at the site reveals abandoned drums showing signs of rusting and a sharp smell of chemicals. The wastes from the two companies include the following chemicals: PCBs, Chromium waste, Acrylamide and Toluene diisocyanate (TDI).

According to Petulla (1988), industrial chemicals form a great risk to the environment if not properly disposed depending on their chemical composition and nature. The effect would be determined by their toxicity level and environmental exposure period. Our case scenario indicates a formally active industrial site and a chemical disposal site with clear signs of leakages most probable an illegal dumping in nature. It would be important in this report to analyze the chemical reaction nature of the wastes involved and expected effects to the environment keeping in mind the stream aquatic life and the human livelihood downstream.

PCBs

PCBs generally refers polychlorinated biphenyls, a human manufactured organic group of chemicals of chlorinated hydrocarbons with chemical formula C₁₂H_10-xCl_x. These chemicals are basically used in electrical transformers and capacitors, oil paints, hydraulic systems oil, rubber products, dye pigments and carbon paper. The most common trade name of PCBs is Aroclor. PCBs naturally undergo cycles in the environment through air, water and in the soil. PCBs components do not readily breakdown and it is anticipated that once in the environment it would stay for longer periods. In our case PCBs would probably leak into the stream and be transported downstream in lighter PCBs quantities to the furthest downstream from the source point of contamination. PCBs have capabilities to accumulate on plant parts for example on the leaves and also be absorbed into bodies of organisms. In our case scenario the human activity downstream include fishing and irrigation of food crops, PCBs in the stream water can be easily absorbed into the fish and also accumulate on the food crop being irrigated. In the case that PCBs leak into the stream it would be dangerous to the human life with great risks of cancerous infections and adverse effects on the immune system, endocrine system and reproduction system (Barry, 1986).

Chromium

Lenssen (1991) wrote that , Chromium 3 which is naturally available is of significant nutritional importance unlike chromium 6 which is an industrial product that has severe human health implications. Chromium is required in very small amount in the human body. Chromium chemical properties make it an industrial utility in steel, dye, leather and wood industries. Human health is contaminated by chromium through breathing and ingestion either in food or through water. In our case scenario, contamination of the stream water upstream by the chromium components is likely to be realized downstream. Chromium contact with human is likely to be realized through ingestion of the irrigated food crops and drinking of water from the stream. Health effects likely to be realized include liver inflation, chrome ulcers and ulcers of the hand and nose. The latency period of chromium due to exposure is usually fifteen to twenty years, this exposure is short-term and does not build-up with time. Human body cells have the tendency to readily absorb chromium-6 which is converted to chromium-3 in the tissues and an excess of chromium is a health risk. It is important to note Chromium-6 is also a carcinogen that is inhaled and can result to lung cancer (Saleska, 1989).

Acrylamide

Acrylamide, a chemical compound is also referred to as prop-2-enamide and has the chemical formula C₃H₅NO. Acrylamide is prepared by hydrolysis and can dissolve in water, chloroform and ethanol. Acrylamide can decompose in the absence of heat forming ammonia producing carbon oxides and oxides of nitrogen. Although most cases of exposure to acrylamide is through food that we eat, its presence in the food has been present in many years and it is most unlikely due to contamination. This largely indicates that it is most unlikely that the presence of acrylamide upstream would cause great harm to the lives down stream as a result of the irrigated food intake because most of the acylamide is formed in the process of cooking, although direct exposure through the dissolved acrylamide is of great concern. Research indicates that acrylamide causes cancer and is harmful to reproductive and nervous systems.

Toluene diisocyanate

Toluene diisocyanate exists in two isomers 2,4-TDI and 2,6-TDI and is produced through reaction of polyolse.Direct exposure and ingestion of Toluene diisocyanate is harmful to the human body depending on the amount of Toluene I ne diisocyanate involved and the exposure build-up Toluene diisocyanates in the body. Reaction with water forms polyureas and carbon dioxide gas. In the case of the disposal, it would partition into the stream water where hydrolysis would take place depending on the water pH and turbidity of the water forming inert ureas. In the presence of light photolysis would take place with high oxidation and its transportation would thus be limited to the area of effluent. Exposure to toluene diisocyanates can lead to harmful effects on the respiratory tract, skin, eyes, and gastrointestinal system. It is known to cause bronchial asthma and dangerous to the aquatic life. Its presence in the stream would be therefore a risk to the human life downstream and the aquatic life present (Neblett, 1994).

Risk assesment

Risk assessment of the site basing on the four steps of risk assessment was done and it involved the following:

1. Identification of the chemicals of study that were considered hazardous and they included the following chemicals; PCBs, chromium waste, Acrynalide and Toluene diisocynate. The samples of the chemicals were taken from the site and its effects determined to include exposure to cancer, weakening of the immune system, damage of the reproductive system and hindrance to photolysis in plants.
2. An assessment of the exposure of human beings on the site revealed that people who just started eating fish from the river downstream were exposed to a high content of PCBs. The PCBs are absorbed by the body of fish and accumulated by plants that are irrigated downstream. Hence exposure to it arises when the fish or plants is consumed. Chromium is most likely taken into the body through foods that are irrigated by water downstream and also by consumption of the water. Human beings are exposed to acrylamide through the irrigated foods downstream and the harmful product is formed when food is cooked. Toluene diisocyanate is exposed by its ability to alter the pH of water thereby forming inert ureas which alters the process of photolysis.
3. PCBs exist in the environment as a combination of congeners but totally different from commercial mixtures. Over time, its composition changes by transformation of chemical components and partitioning. An assessment of the dose response of cancer is done with full consideration of the toxic levels and the activities of human population in the environment. In order to determine the effects of chromium waste, samples of urine are taken from people living near the dump site and compared to people living far from dump sites. The results show that, people living near the dump sites have high levels of chromium, nearly seventy five percent more than those living far away. For Acrylamide, its dose response effects are assessed using rats. Rats exposed to high doses of acrylamide and are observed to have swelled thyroid glands and growth of tumors in its body parts.
4. Lastly, risk characterization would involve evaluating the hazards of the chemicals found in the site, their exposure response and coming up with necessary remedies for the site.

Recommendation

In order to properly manage waste sites, managers of the environment and the public need to design protective measures to manage waste sites, surface impoundments and set aside site units of the wastes. Using this approach will help the stakeholders come up with systems that that consider all aspects of pollution. Focus should be emphasized on ground water and air circulation models.

References

Barry, J. (1986) Solving the Hazardous Waste Problem,Washington, DC: EPA.

Lenssen, N. (1991) Nuclear Waste: The Problem that Won’t Go Away, Washington, DC: WorldWatch Institute.

Neblett, A. (1994) Forces of Change: Shaping the Future of Texas, Austin: TCPA.

Petulla, J. (1988) American Environmental History, Columbus, Ohio: Merill Publishing Company.

Saleska, S. (1989) Nuclear Legacy, An Overview of the Places, Problems and Politics of Radioactive Waste, Washington, DC: Public Citizen.