The Effect of Environmental Contaminants on Animal Health

Convener: Dorit Kalo, The Hebrew University of Jerusalem

Human and animal health can be affected by various environmental stressors. While much attention has been paid to the increase in ambient temperature, i.e., global warming, less attention has been given to environmental contamination and its consequences on animal health. Environmental contaminants are defined as physical, chemical, biological or radiological substances that have an adverse effect on living organisms. Contaminants can be classified into two major categories: human-derived (or manufactured) and naturally occurring. There are more than 85,000 human-derived chemicals in the environment that are defined as environmental contaminants. Human-derived products are used for industrial applications (metal metalloids, polycyclic aromatic hydrocarbons, perfluorinated compounds, plastics, radioactive elements) or agricultural products (pesticides, herbicides). Human-derived contaminants also include persistent organic pollutants, and pharmaceutical and personal care products. Naturally occurring compounds are defined as products that are frequently in the environment without human intervention. These include compounds from biological sources, such as mycotoxins produced by fungi, chemicals of plant or soil origin (e.g., lead, arsenic) and those from physical sources, such as metal, glass and gas (e.g., radon). The main concern is that not all naturally occurring compounds have been identified and, therefore, are not included in routine monitoring programs. Overall there is a great concern because there are environmental contaminants in the air inhaled, water consumed, soil where animals are pastured or that is used to produce the feed consumed by animals.
Some of these contaminants are defined as endocrine-disrupting chemicals (EDCs) and are thought to deleteriously affect both male and female fertility for instance. Environmental contaminants differ in mode of action having a molecular, cellular and/or endocrinological effects resulting in alterations, resulting in different physiological and/or behavioral outcomes and adverse consequences to human and animal health. For example, EDCs have effects in modulating endocrine functions and consequently affect reproduction, neurol functions, embryo/fetal development and immunity. Other contaminants, such as mercury and arsenic, are also associated with neural system functions. Arsenic, cadmium, heavy metal and lead intake and residuals in the body are associated with cardiovascular diseases and gaseous chemicals, such as polycyclic aromatic hydrocarbons induce respiratory dysfunctions.