Climate Change’s Effect on Indirect Exposure to Agricultural Pathogens/Chemicals

Linda’s comment:  Here is proof how deady Agricultural Pathogens and Chemicals are for our bodies.  This shows you the importance of eating non-GMO and eating organically.  Not just eating but inhalation of particulates or volatiles will fill us with carcinogens. Plus,  mycotoxins, microcystin), which further complicates the picture.  Where will this all STOP?  We need to start speaking up folks.  How many of you live near these toxic fields of crops?

Regards,
Linda

Effects of Agricultural Chemicals and Pathogens on Human Health

Humans may be exposed to agriculturally derived chemicals and pathogens in the environment (i.e., air, soil, water, sediment) by a number of routes, including the consumption of crops that have been treated with pesticides or have taken up contaminants from soils; livestock that have accumulated contaminants through the food chain; fish exposed to contaminants in the aquatic environment; and groundwater and surface waters used for drinking water. Exposure may also occur via the inhalation of particulates or volatiles, or from direct contact with water bodies or agricultural soils (e.g., during recreation). The importance of each exposure pathway will depend on the pathogen or chemical type (Table 1). The main environmental pathways from the farm to the wider population will be from consumption of contaminated drinking waters and food. In the United Kingdom, vector, aerial, and direct contact pathways are currently of less importance to the general population.

Evidence for adverse human health effects from agricultural contaminants comes from epidemiologic studies (occupational and general population studies), case and outbreak reports, and toxicologic assessments. Attributing health effects in the general population to specific agricultural contaminants is often difficult because multiple chemicals and pathogens are in the environment, with multiple routes whereby they may reach humans. Some naturally occurring chemicals are also harmful (e.g., mycotoxins, microcystin), which further complicates the picture.

Although often inconclusive, several studies have associated different health outcomes with exposure to chemicals from agriculture. For example, Parkinson’s disease has been linked with exposure to pesticides (Ascherio et al. 2006), and studies have suggested that repeated exposure to low levels of organophosphates may result in biochemical effects in agricultural farmworkers (e.g., Lopez et al. 2007), as well as enhanced risks of certain cancers, such as leukemias or lymphoma. Studies in North America have associated chlorphenoxy herbicide exposure with circulatory and respiratory malformation, congenital abnormalities, urogenital and musculoskeletal anomalies, and changes in the male:female sex ratio of offspring (Stillerman et al. 2008).

Outbreaks of waterborne disease from the contamination of water supplies with animal waste (often associated with water treatment failures) remain an important public health problem (Crowther et al. 2002). Cryptosporidium transmission in humans has been linked to areas where manure is being applied to land (Lake et al. 2007a). There is also good evidence that heavy rainfall increases the risk of sporadic cases of Cryptosporidium in England (Lake et al. 2005, 2007b). Exposure to Mycobacterium avium in agricultural systems has been associated with Crohn’s disease, although the mechanism is not clear (Pickup et al. 2005).

Agricultural chemicals may also indirectly affect human health via other, often unanticipated pathways. Examples include dispersal of biotoxins into coastal communities resulting from harmful algal blooms triggered by inputs of nitrates from agriculture (Codd et al. 2005; Fleming et al. 2006; Kirkpatrick et al. 2006) and the agricultural use and environmental occurrence of antibiotics that may facilitate the selection of antibiotic resistance in microbes in the soil and water environments (Boxall et al. 2003).