Pesticides are chemicals
made to poison insects, weeds or other pests. Most pesticides are
also poisonous or harmful to humans if they get on the skin, or
if they are breathed into the lungs in the form of gases, fumes,
dust or fine spray droplets, or if they are swallowed.
These are some of
the ways people may be poisoned:
Poisoning
at work
Many chemicals that
are made, used, or stored in workplaces are poisonous. People who
work with these chemicals need to know how to handle them safely
to avoid being poisoned.
Sometimes workers
may not know that they are handling a poisonous chemical, or they
may know that the chemical is poisonous but not have been told or
shown how to handle it safely. They may not have read the label
or the safety information. Sometimes they may know the dangers but
be too lazy or careless to use safe methods.
Accidents, fires or
explosions at work may result in chemicals spilling or leaking out
of their containers onto roads or into rivers, or vapours and gases
being released into the air. Sometimes chemicals spread over a large
area and poison many people.
Chemical waste and
empty chemical containers may be serious safety hazards if they
are not dealt with in the right way.
Carbon
monoxide poisoning
When oil, gas, wood,
coal or other fuels burn they give off a gas called carbon monoxide,
which can cause serious poisoning and often causes death. This can
happen when fires, stoves, heaters, or ovens are used in rooms,
huts or tents where there is no open window or chimney to let fresh
air in and carbon monoxide out. Petrol engines also give off carbon
monoxide, and people may be poisoned if they run a car engine inside
a garage when the doors are shut.
Self-poisoning
People may try to
harm themselves by deliberately taking poison - this is called self-poisoning.
In some countries people take medicines to poison themselves, but
people living in rural communities are more likely to take pesticides.
People suffering from
depression, serious illness, or alcohol dependence may try to kill
themselves by taking poison. They may swallow large amounts of medicine,
pesticide or other poisons. If they recover they might try to poison
themselves again unless they receive appropriate treatment.
Many young people
who try to poison themselves are unhappy because of problems they
do not know how to deal with, such as unhappy love affairs or arguments
with boyfriends or girlfriends.
Using
poison to harm other people
Sometimes people use
poison to harm others. They may do it as a joke or they may want
to frighten or even kill a person. If you have evidence that this
is happening or has happened, tell the police.
Poison
in food or drink
Food or drink can
be contaminated by poison from microscopic organisms such as bacteria,
viruses, or mould, or by chemical poisons.
Some plants, mushrooms, animals or sea-creatures contain poisonous chemicals. Poisons made by plants, animals or microorganisms are
called toxins.
Poisons
made by microscopic organisms
Food may be contaminated
by bacteria before or after cooking, during preparation or storage,
by contact with hands that have not been thoroughly washed, or with
contaminated surfaces, containers or kitchen utensils. It may also
be contaminated by animals or insects, particularly flies. Heating
food thoroughly destroys most - but not all - bacteria and bacterial
toxins. However, if cooked food is kept warm or at room temperature
for any length of time, any bacteria present will multiply and may
cause disease.
Moulds grow on foods
that are damp or damaged by insects, and some moulds produce poisons.
Moulds growing on nuts or grain that has been gathered and stored
before it is dry may cause serious poisoning. Some ways of drying
and preserving food do not stop moulds growing on the food.
People can catch diseases
from eating food infected with worms or other organisms, but this
is not poisoning and is not dealt with in this book.
Chemical
poisons
There are many ways
chemical poisons can get into food and drink, for example:
-
when people working with chemicals eat in the workplace or do
not wash their hands before eating;
-
when chemicals spill onto food as it is being moved from place
to place, or when it is in a storeroom;
-
when food or drink is stored or cooked in containers that are
contaminated with chemicals;
-
when people make flour from grain that has been treated with
pesticide because it was meant to be used for seed or bait,
not for food;
-
when people brew their own alcoholic drinks and produce poisonous
alcohols, such as methanol;
-
when water supplies are polluted by accidental spills of chemicals,
or by chemical waste from factories or waste dumps near watercourses.
Poisonous
plants, mushrooms, animals and sea-creatures
Some plants, mushrooms,
animals and sea-creatures contain toxins. Sometimes it is very hard
to tell the difference between plants or fish that are good to eat
and those that are poisonous.
Medical
poisoning
Sometimes people are
poisoned by medicines given to them by a doctor or another health
care worker. They may be given the wrong medicine or be given the
wrong dose of the right medicine. There are many reasons why this
can happen. The doctor may not know the patient is allergic to a
medicine, or may give the wrong dose because of a mistake in measuring
it.
Abuse
of drugs, chemicals or plants
People may take drugs
to change their mood or behaviour, to feel relaxed, or to get more
energy. This is called drug abuse because it is not a medical use
of the drug. Some people abuse drugs such as heroin, cocaine or
barbiturates. Drinking too much alcohol is an important kind of
drug abuse.
Other substances may
produce some of the same effects. Some people breathe in chemicals
such as glue, paint, nail varnish remover, cigarette lighter gas,
petrol or dry-cleaning fluid. This is sometimes called solvent sniffing
or solvent abuse. People may breathe fumes from a cloth soaked in
liquid or put chemicals or glue into a plastic bag and breathe deeply
from the bag.
In many societies
people use plants or fungi for their hallucinogenic, stimulant or
relaxing effects. Some plants may be eaten raw, others are cooked,
made into drinks, or smoked. Two plants commonly used in this way
are tobacco and cannabis.
Many of the drugs,
chemicals and plants that are abused are poisonous if people take
too much at one time or use them for many months or years. For example,
alcohol causes liver damage, smoking causes lung cancer and cannabis
can affect people's memory.
The
benefits and dangers of using chemicals
All countries use
a large number of different chemicals in agriculture, in industry,
in medicines and in the home. There are many good reasons for using
them. Pesticides and fertilizers have helped farmers grow more crops.
Medicines can cure or prevent disease, and they can give people
longer and more comfortable lives. Cleaning products have made household
tasks easier.
Useful chemicals can
also be dangerous. People may have to use amounts that could be
poisonous if they got into the body. Some chemicals can also cause
harm if they get into the air people breathe, into the soil where
people work or grow food and animals live, and into the rivers and
streams that supply water for drinking, washing, or irrigating crops.
The danger can be made smaller if chemicals are used safely, and
efforts are made to prevent accidents, but the danger will never
completely go away.
Communities must decide
whether the benefit of using the chemicals is large enough and the
danger small enough for them to live with. There are many things
to think about:
-
How useful is the chemical?
-
What kind of harm can the chemical cause?
-
Will the chemical affect the environment?
-
Can the chemical be handled safely?
-
How many people will use the chemical, and how many people might
be exposed to it because they work or live near the place it
is made or used?
-
Can a less poisonous chemical be used instead?
-
How much money could be saved by using the chemical and how
much would it cost to stop using it?
