Factors Threatening The Environment: Chemical Risks

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A number of toxic substances that humans encounter regularly may pose serious health risks. Pesticide residues on vegetable crops, mercury in fish, and many industrially produced chemicals may cause cancer, birth defects, genetic mutations, or death. Many chemicals have been found to mimic estrogen, the hormone that controls the development of the female reproductive system in a large number of animal species. Preliminary results indicate that these chemicals, in trace amounts, may disrupt development and lead to a host of serious problems in both males and females, including infertility, increased mortality of offspring, and behavioral changes such as increased aggression.

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