Generally, the toxicology will affect the Municipal Solid Waste (MSW) that involves batteries, water bottles, paints, light bulb and many more that used in daily life. As we know, these waste products decomposed and it may cause in deposition of chemicals in low concentration. When the concentration become low, it will affect adversely to heavy metal, metalloids, plant, soil organisms, water quality, and animal health and last but not least is human health and it may have a negative side effect on the environment as well.

 

1.  LANDFILL

1.      The effects on water quality

There is a possibility that leachate from the municipal solid waste leached into the soil even it is a sanitary landfill if it is not well maintained. When leachate leached into the soil by rain water, the leachate will get mixed up with the ground water. As we all know that municipal comprise of varieties of waste including household hazardous waste and the toxic content of household hazardous waste will contaminate the ground water and will affect the water quality and this will directly put humans and other living organism in the soil at high risk of health.

2.      The effects on soil organism

Disposing solid waste to the land increase the amount of toxicity in the soil. Soil organisms such as worms will then consume this contaminated soil, which then will increase the amount of cadmium or nickel in these organisms. When the metal content in the soil crosses its maximum limit, it will results in the death of these organisms. Apart from soil organisms, it is also harmful for other animals and children who have direct consumption of this contaminated soil.

3.      The effects on plant growth

Municipal solid waste contains boron, which suppresses plant growth. This toxicity can be overcome by leaching of municipal solid waste. Boron is soluble in water, is washed away from the soil by continuous leaching. Cadmium, lead and mercury are also harmful for plants even at low concentrations. Elements like arsenic, copper, chromium, nickel and zinc are present in very low concentrations. These metals are taken up by plants.

2. COMPOSTING

I.                   The effects on soil chemical properties

It modifies and stabilizes the soil pH as it increases the cation exchange capacity in the soil (CEC). Composting also provide nutrients to the soil, such as the source of nitrogen, phosphorous, potassium and macronutrients while organic nutrients are mineralized over time.

II.                The effects on soil biology

Composting stimulates microbial growth and activity in the soil biology. It may change the species composition in the soil. Composting will also promotes the population growth of earthworms. It may suppress plant diseases.

III.             The implications for plants

Greater microbial biomass and activities can increase the availability of nutrients to plants and promote the formation and stabilization of soil aggregates and better soil structure. Composting also makes possible link between microbial community composition and suppressiveness of soils to plant disease.

 

            Incinerations are one of the problems that relates to the toxicology. Incineration is a waste treatment technology that process wastes involving the combustion of organic substances contained in waste materials. The toxicity of combustion emissions from a municipal incineration plant had been identified due to health problem in some place. It was tested in a series of rapid test methods and it concern about cellular energy metabolism, cellular detoxification and mutagenicity. And almost all of the outputs of incinerations are release a deadly chemical that causes a myriad of disorders, as in sicknesses that nurses work so diligently to treat. The United States Environmental Protection Agency (EPA) had been exposed about the hazards of dioxin in 1994 and it was issued a critical report on the substance.

            Furthermore, PVC plastic is incinerated as a medical waste disposal method, dioxin is created as an unintended by-product. Let?s say as dioxin is also created throughout the life cycle of chlorinated plastic, the EPA currently cites medical waste incinerators as the third largest source of dioxin production. Incineration is an unsolved problem of waste and it will reduce waste to approximately 30 - 50 % of the original compressed waste mass. This is converted into an ash that contains some of the most toxic concentrations of substances, such as dioxins and heavy metals. This toxic waste is very problematic for the generation and safe disposal as pollutants from landfill sites have been known to seep out, polluting local water sources, and once they contaminate the water table, their removal is considered to be almost impossible. It have been stated by the EU Commission that this may be one of the most important sources of dioxins in the future. Moreover, the accidents are also a possibility when moving toxic ash on lengthy road journeys to special landfill sites.

 

            In addition, incinerators release hundreds of toxic chemicals into the atmosphere when the waste is burned and in fact, it will because health effects and some of the most important constituents of emissions are considered to be particulates, heavy metals and combustion products of man-made chemicals. Predominantly, the toxins released by incinerators can cause damage to the immune system as it thought that the synergistic effect of the combination of various toxins is to be expected to have an even more potent and damaging effect on immunity than any pollutant in isolation. Almost all of these chemicals are fat-soluble and accumulate in the fatty organs and tissues. Particularly, the heavy metal dangerous to the unborn child because many of these toxins are actively transmitted to the foetus across the mother?s placenta, for the body mistakes heavy metals for essential minerals. Until very late in the pregnancy, the only fatty tissues that the foetus has, is its nervous system and particularly the brain, so it is there that they accumulate.