Environmental Ecotoxicology is the study of the harmful effects of chemicals on public health, animals and natural environment especially at the population, community, ecosystem and biosphere levels. Ecotoxicology integrates from toxicology and ecology. All organisms are interconnected in the web of life. If a chemical affects an organism, the organisms will suffer and consequently all the living beings in the ecosystem will be the victims as all are interdependent.
Environmental toxins can have many detrimental influences on human health, fertility and reproduction. There are more than 400 environmental chemicals or their metabolites found in human samples. Hazardous chemical health effects are poisoning, breathing problems, skin rashes, allergic reactions, allergic sensitisation, cancer, and other health problems.
Ecotoxicological effects on organisms, or at other levels of biological organisation, resulting from exposure to a chemical. These levels may include cellular level, individuals, populations, communities and ecosystems and finally, landscapes. According to the global health body, 2 million lives and 53 million disability-adjusted life-years were lost in 2021 due to exposures to chemicals. Air pollution alone causes over 6·5 million deaths each year globally and this number is also increasing.
Chemicals can enter and irritate the nose, air passages and lungs. Inhalation is the most common route of a chemical to enter the body. They can become deposited in the airways or the lungs and then into the bloodstream carrying to the rest of the body. Ingestion of food, drink or other substances is another route of exposure. The average person is now exposed to more than 700,000 toxic chemicals a day. From perfumes to cleaning products, from cosmetics to plastic water bottles, much of our everyday life is always exposed to chemicals that aren't good for health.
Accidents or incorrect use of household chemical products may cause immediate health effects, such as skin or eye irritation or burns or poisoning. There can also be longer-term health effects. Chemical pollution also affects the delicate balance of the Earth's ecosystems. The presence of heavy metals like cadmium, mercury and lead can affect soil quality and reduce the number of micro-organisms that support the soil fertility and production.
Animals can go to the brink of extinction because of the break in the food chain. Plants absorb toxins through their roots and leaves. Thus, animals and humans are saved from the fatal effects of chemical exposure.
Animals and humans eat other animals or plants that are already poisoned, which will continue the spread of chemicals as a secondary poisoning. Chemicals induce significant mortality but make the organism sick or make it change its behavior.
With chronic use of pesticides, causes the risk of abnormalities in chromosome structure in humans, as well as affecting the reproduction, nervous and cardiovascular system. The genetics can be affected by toxicants to the DNA leading to mutations.
Pesticides found in fruits, vegetables and meats are used widely for preventing, destroying, or repelling the insects which are considered harmful but we are compelled to use to meet the growing demand. Plants are affected if their pollinators or seed-dispersers are killed.
Predator-prey relationships are also affected by toxins either surpassing the predator or the prey resulting in imbalance in the ecosystem and resources of the area. A community that is species-rich will have a better chance of recovering from an exotoxin disturbance, rather than a community that is not species-rich. Species richness and diversity is essential for maintaining a healthy, well-balanced ecosystem.
Chemicals are shown to prohibit germination and growth of plants. Plants are the primary producers and are at the bottom of the pyramid. Thus every organism in the ecosystem relies on the health and abundance of the plants for their survival. If plants are battling for survival due to the chemical exposure, other organisms will either die because of starvation or due to the direct effects of the chemicals.
To fight back chemicals, we can reduce our use; using less can have a big impact on the amount of chemicals that reach the environment. Use only natural, plant-based biodegradable products. Micro-fibre cloths, for example, can clean everything just with water without chemicals. Companion planting can control pets and insects. Use only the plant-based composts for gardens and fields.
Ecotoxicologists help to protect the environment and existing ecosystems for future generations. They also make important contributions to protect the food resources and the ecosystems around the world. The ultimate goal of Ecotoxicology is to reveal the effects of chemicals to other environmental factors and to find out the most effective preventive measures for the future. We can make changes to reduce the impact of chemicals on our environment if we are aware and act now, then we can protect mother nature for the future generations.
