Agricultural activities, chemicals from pesticides

Primary organics are emitted to the atmosphere by industrial sources (oil refineries, chemical plants, producers and users of solvents and plasticizers), vehicles (as a result of incomplete fuel combustion, oxygenated degradation products of lubricating oil, polymers from tires), and agricultural activities (use of pesticides). An exhaustive literature survey is beyond the scope of this section, but can be found in Air Quaiity Criteria for Particulate Matter many useful references are also available. 

This high agriculture activity compromises the chemical and ecological status of the Ebro delta. Pesticides used in the area migrate into the delta building up, together with the pollution produced by some industries, a contamination that can be dangerous to its both fauna and flora, and this contamination increases when water from the rice fields is drained into the delta [17]. 

Chemicals from agricultural activities (including pesticides)... 

Wildlife associated with agricultural activities are more likely to be exposed to pesticides than those distant from human habitat. Aquatic species living in estuaries are more likely to contain chemical pollutants than those found in mountain lakes and streams. Moreover,... 

Pesticides commenced from their manufacture in organic synthesis chemical plants. In 1939, the USA Agricultural Department recorded 32 pesticides, whereas in 1987 the US EPA catalogued 1200 active compounds with insecticide action, formulated in 37,000 commercial products. 

An important aspect of environmental fate are transfer processes, which convey chemical from one phase to another (Fig. 4). Of particular importance are transfer processes between the atmosphere and the Earth s surface and between the water column and underiying sediments. For example, a pesticide molecule may evaporate from an agricultural field into the atmosphere and be deposited to a lake or the ocean further downwind. A heavy metal may be transferred between the water column of a lake and its surface sediment as particles settle and resuspend in response to varying biological activity and water turbulence. 

Substances hazardous to health include substances labelled as dangerous (i.e. very toxic, toxic, harmful, irritant or corrosive) under any other statutory requirements, agricultural pesticides and other chemicals used on farms, and substances with occupational exposure limits. They include harmful micro-organisms and substantial quantities of dust. Indeed any material, mixture or compound used at work, or arising from work activities, which can harm people s health is apparently covered. 

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