such as the organochlorine insecticides have been found to result in concentrations in
fish-eating birds that far exceed levels acceptable for human consumption.
This magnification occurs when a substance is not excreted as rapidly as it is
ingested. The concentrated dose is then passed on to its predator in the food chain,
which in turn concentrates the substance further. These are the effects that are so
difficult to access since an actual lethal effect may not appear until several or many
years after exposure to the pesticide.
9.4 Toxic Effects on Human Health
Although beyond the scope of this chapter, one must express concern about the
possible human health problems that can arise from the application of chemical
pesticide poisons to the environment in pest and vector control.
Toxic effects on human health may be acute, chronic, carcinogenic, mutagenic, or
teratogenic. A human health risk evaluation or assessment can inform the level risk
of a single chemical based on the level of human exposure, toxicity of the chemical,
and sensitivity of the target (child vs. adult). Cocktails of chemicals are not typically
assessed using this methodology, but is more representative of the real risk, as
chemicals do not occur in nature in isolation from each other.
Acute effects imply that the effect is elicited rather quickly (within hours to a few
days) following exposure. The acute effect may range from a mild headache and
discomfort to death. Chronic effects occur following long exposure to a chemical.
Chronic effects are exemplified by chemically induced liver cirrhosis and ulcers.
Carcinogenic and mutagenic effects involve the alteration in the DNA of a cell.
Teratogenic effects involve the effects a chemical may have on a developing
embryo. For example, neurological effects of DDT and its by-products have been
suggested to have linkages to Alzheimer disease occurrence [15].
Among the chemicals that humans handle, organophosphorus insecticides rank
high among occupational poisonings. High-risk groups include pesticide manufacturers and spray operators. The organophosphates have been largely replaced since
the 1990s by the neonicotinoids in the United States.
While an important and active area of research and policy, further discussions on
human health risk assessment of acute or chronic effects of chemical pesticides are
beyond the scope of this chapter.
10 In Summary and Other Considerations
Coupled with preventative programs for environmental control and consideration of
externalities of fate and transport in the environment, as well as, pesticide trace food
residues and human health effects, pesticide-based control of pests and vectors is a
necessary approach to protect human health and the economy. Within the limitations
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L. S. Clesceri and E. J. Clesceri
fish-eating birds that far exceed levels acceptable for human consumption.
This magnification occurs when a substance is not excreted as rapidly as it is
ingested. The concentrated dose is then passed on to its predator in the food chain,
which in turn concentrates the substance further. These are the effects that are so
difficult to access since an actual lethal effect may not appear until several or many
years after exposure to the pesticide.
9.4 Toxic Effects on Human Health
Although beyond the scope of this chapter, one must express concern about the
possible human health problems that can arise from the application of chemical
pesticide poisons to the environment in pest and vector control.
Toxic effects on human health may be acute, chronic, carcinogenic, mutagenic, or
teratogenic. A human health risk evaluation or assessment can inform the level risk
of a single chemical based on the level of human exposure, toxicity of the chemical,
and sensitivity of the target (child vs. adult). Cocktails of chemicals are not typically
assessed using this methodology, but is more representative of the real risk, as
chemicals do not occur in nature in isolation from each other.
Acute effects imply that the effect is elicited rather quickly (within hours to a few
days) following exposure. The acute effect may range from a mild headache and
discomfort to death. Chronic effects occur following long exposure to a chemical.
Chronic effects are exemplified by chemically induced liver cirrhosis and ulcers.
Carcinogenic and mutagenic effects involve the alteration in the DNA of a cell.
Teratogenic effects involve the effects a chemical may have on a developing
embryo. For example, neurological effects of DDT and its by-products have been
suggested to have linkages to Alzheimer disease occurrence [15].
Among the chemicals that humans handle, organophosphorus insecticides rank
high among occupational poisonings. High-risk groups include pesticide manufacturers and spray operators. The organophosphates have been largely replaced since
the 1990s by the neonicotinoids in the United States.
While an important and active area of research and policy, further discussions on
human health risk assessment of acute or chronic effects of chemical pesticides are
beyond the scope of this chapter.
10 In Summary and Other Considerations
Coupled with preventative programs for environmental control and consideration of
externalities of fate and transport in the environment, as well as, pesticide trace food
residues and human health effects, pesticide-based control of pests and vectors is a
necessary approach to protect human health and the economy. Within the limitations
408
L. S. Clesceri and E. J. Clesceri