144 Ecology and Applied Environmental Science
Organophosphates, such as parathion and malathion, and carbamates have
been used to replace the chlorinated hydrocarbons. Most of them inactivate
the enzyme cholinesterase, which is involved in the chemical transmission of
nerve impulses. They are characterised by significant to very high toxicity,
the organophosphates in particular, but are more or less unstable and thus
in principle they do not tend to accumulate, to display biomagnification or
to cause long-term damage to organisms. Other serious hazards for people
and ecosystems are some insecticides, which poison all living organisms and
are capable of penetrating all tissues of plants and animals, killing even the
organisms that feed on such plants and animals. Rachel Carson, author of
Silent Spring, compares them to the magic dress the sorceress Medea, wife
of Jason, gave to her rival, who died in excruciating pain.
Failure of workers in agriculture and industry to heed warnings, failure
to take protective measures (masks, clothing, provision for wind direction),
and high temperatures increase the risks of pesticide use. Poisoning occurs
mainly in the following ways:
• Exposed farmers when mixing and applying pesticides, workers on
the land who enter fields after pesticides have been applied, and workers in the production and packaging industry are at greatest risk. Even
farmers who are well aware of the harmful effects of pesticides are
sometimes unable to translate this awareness into their practices.
It has been estimated that a high percentage of accidents and poisonings are occupational.
• Accidental ingestion of pesticides by children or other family members and the use of pesticide containers to store or transport food are
other means of poisoning.
• Consumption of recently sprayed produce that has been channelled
onto the market may lead to poisoning. This phenomenon is common
in countries where farmers do not observe the harvest restrictions
but pick their produce, mainly fruit and vegetables, immediately after
spraying, if better market prices develop.
After the negative aspects of the indiscriminate use of biocides were discovered and following the first ban on chlorinated hydrocarbons (in 1969 in
the United States), efforts towards better control of the production and use
of pesticides were stepped up internationally, under pressure from groups
of scientists and activists.
It can be argued that the organophosphates, carbamates, and even other
non-persistent biocides are an indispensable solution to the problem of controlling harmful organisms, provided that they are used with care so as to
avoid direct toxic effects on humans and animals. However, as with the
chlorinated hydrocarbons, their use has not only direct but also a multitude
of indirect consequences. The biocides disturb crucial relationships among
Organophosphates, such as parathion and malathion, and carbamates have
been used to replace the chlorinated hydrocarbons. Most of them inactivate
the enzyme cholinesterase, which is involved in the chemical transmission of
nerve impulses. They are characterised by significant to very high toxicity,
the organophosphates in particular, but are more or less unstable and thus
in principle they do not tend to accumulate, to display biomagnification or
to cause long-term damage to organisms. Other serious hazards for people
and ecosystems are some insecticides, which poison all living organisms and
are capable of penetrating all tissues of plants and animals, killing even the
organisms that feed on such plants and animals. Rachel Carson, author of
Silent Spring, compares them to the magic dress the sorceress Medea, wife
of Jason, gave to her rival, who died in excruciating pain.
Failure of workers in agriculture and industry to heed warnings, failure
to take protective measures (masks, clothing, provision for wind direction),
and high temperatures increase the risks of pesticide use. Poisoning occurs
mainly in the following ways:
• Exposed farmers when mixing and applying pesticides, workers on
the land who enter fields after pesticides have been applied, and workers in the production and packaging industry are at greatest risk. Even
farmers who are well aware of the harmful effects of pesticides are
sometimes unable to translate this awareness into their practices.
It has been estimated that a high percentage of accidents and poisonings are occupational.
• Accidental ingestion of pesticides by children or other family members and the use of pesticide containers to store or transport food are
other means of poisoning.
• Consumption of recently sprayed produce that has been channelled
onto the market may lead to poisoning. This phenomenon is common
in countries where farmers do not observe the harvest restrictions
but pick their produce, mainly fruit and vegetables, immediately after
spraying, if better market prices develop.
After the negative aspects of the indiscriminate use of biocides were discovered and following the first ban on chlorinated hydrocarbons (in 1969 in
the United States), efforts towards better control of the production and use
of pesticides were stepped up internationally, under pressure from groups
of scientists and activists.
It can be argued that the organophosphates, carbamates, and even other
non-persistent biocides are an indispensable solution to the problem of controlling harmful organisms, provided that they are used with care so as to
avoid direct toxic effects on humans and animals. However, as with the
chlorinated hydrocarbons, their use has not only direct but also a multitude
of indirect consequences. The biocides disturb crucial relationships among