The conflict of human convenience and the wellbeing of ecosystems is a repeating issue. Parathion (usually referring to ethyl parathion, sometimes methyl parathion), is an effective insecticide and one of the most toxic organphosphates, proved to be sometimes fatal to humans and other animals. The original intent for producing and using parathion as an insecticide are not malicious, however with more recent information the risks have become more apparent. The convenience of using parathion is not worth the consequences to natural ecosystems and human health.
An Effective Method
Parathion is an effective and relatively cheap insecticide. It kills unwanted insect 'pests' by disrupting their nerve impulses. Pest control has played a large role in farming and the mass production of food to feed millions of people, and is also part of the monetary success for individual farmers and overall economies. Pesticides are especially needed for monocultures of food that resulted from the Green Revolution of mass factory farming, as an entire culture would be susceptible to unwanted insects. The method of factory farming has helped humans avoid Thomas Malthus' prediction that starvation would overtake the world by the year 2000, however, the use of pesticides is among the many rising issues associated with factory farming, and there are safer options than parathion such as introducing a natural predator or genetically modifying crops so that they are less susceptible to the pest. Many organic farmers have successfully raised crops without the use of any pesticides, as all pesticides do have the potential for adverse side effects. One of the reasons parathion is used is because its high toxicity makes it highly effective, but it also highly effective on other non-targeted species.
A Toxic Threat
Other living things are not immune to the devastating effects parathion has on an organism, Parathion has proven to be especially toxic to birds such as grouse, pigeons, red-winged blackbirds, and sparrows. Amounts of dermal exposure may be fatal for birds such as house sparrows, which have 50% mortality rate after 24 hours of dermal exposure of 1.8 mg / kg on their feet. Not only do they receive exposure through the air when it is sprayed, but also because of what they prey on. Ethyl parathion has been pinned as the direct cause of death for birds in numerous instances, for example the death of fourteen Mississippi kites from insects that were contaminated by parathion in a nearby cotton field in 1994. Another occurrence was in 1982, New York, when almost 3200 birds of various species were found dead in a field containing scattered rye seeds contaminated with ethyl parathion. As birds consume contaminated seeds and insects, bioaccumulation and biomagnification occur and the buildup of parathion in their systems often kills them, and can also impair some birds exposed to nonlethal doses in terms of ability to avert predators, and reproductive behavior (such as with the mallard and bobwhite) though it is unknown whether or not parathion affects reproductive ability.
Parathion also has the potential to damage ecosystems by damaging other wildlife. Damage to aquatic invertebrates with ethyl parathion occurs with an EC50 at less than 1.0mg/L. On an acute basis it is also toxic to fish, with the potential to throw off the delicate balance of many aquatic ecosystems with water contamination. This would have a negative impact on entire ecosystems and communities whose economies and jobs depend on the fishing industry. Honeybees also play important roles in their ecosystems as pollinators, and they too are highly susceptible to the toxicity of parathion. Pollinators are necessary for growing plants in both natural ecosystems and in growing crops for humans in farms.
Humans are also vulnerable to the health hazards of parathion, especially those who work with the chemical or live near landfills where it is disposed of. Parathion is a carcinogen and endocrine disruptor, and has been reported to have cause an influenza-like state and has also been associated with indirect brain impairments, such as disorientation, memory loss, decreased ability to concentrate, confusion, and delayed reflexes. It has also been linked with emotional disorders such as severe depression and insomnia. Nerve damage occurs because parathion is a cholinesterase-inhibiting chemical, which prevents the breakdown of acetylcholine when it is no longer needed to trigger physical reponses to nerve impulses. The buildup of acetylcholine causes the impulses to be repeated uncontrollably, with potential direct symptoms such as muscle spasms, trembling, paralyzed breathing, irregular heartbeat, convulsions, involuntary bowel movement, and in the most extreme cases, coma or even death.
Considering evidence proving a direct link between various adverse effects parathion has on the health of other animals such as birds, aquatic invertebrates, fish, pollinating insects, and humans, the risks are obvious and severe. The potentially risks outweigh the benefits of convenience as the real cost goes beyond monetary values, but takes a toll on health of natural ecosystems, humans and other animals.
Sources
Bird Conservancy. (n.d.). Pesticide Profile - Ethyl parathion. abc birds. Retrieved December 12, 2013, from http://www.abcbirds.org/abcprograms/policy/toxins/profiles/ethyl_parathion.html
EXTOXNET. (n.d.). Cholinesterase Inhibition. EXTOXNET. Retrieved December 12, 2013, from http://extoxnet.orst.edu/tibs/cholines.htm
The Encyclopedia of Earth. (2008, August 1). Health effects of methyl parathion Edit Classification Publishing Workflow . The Encyclopedia of Earth. Retrieved December 12, 2013, from http://www.eoearth.org/view/article/153408/
Pesticide Information Center. (n.d.). Parathion. EXTOXNET. Retrieved December 12, 2013, from http://extoxnet.orst.edu/pips/parathio.htm Reuber, M., & Cooper, S. (n.d.). PARATHION (Ethyl parathion). Beyond Pesticides. Retrieved December 12, 2013, from http://www.beyondpesticides.org/pesticides/factsheets/parathion.pdf