How Dangerous is Pyrethrin?
Although pyrethrin is highly toxic to humans and aquatic life, the risk of prolonged exposure is low. Long-term exposure can affect reproductive functions and result in lowered body weight and liver damage. Pyrethrins also have adverse effects on aquatic insects. In one study, pyrethrins decreased the rate at which minnow eggs hatched and water flea young were produced, as well as their reproductive performance.

Nevertheless, there are concerns about pyrethrins and other similar chemicals in household cleaners. In the early 20th century, studies linked pyrethrins to allergic reactions were conducted. These studies, however, were conducted on crude pyrethrin extracts and may have included impurities that contributed to allergic reactions. These impurities are now removed through refinement. That said, warning labels on non-pesticide products may confuse the public and cause false alarms for a relatively harmless chemical.

Scientists are also paying attention to the effects of pyrethrins and pyrethroids on children. A study published by Emory University in 2006 found that even children eating an organic diet had pyrethroid metabolites in their systems. This is largely due to the fact that children's bodies are more vulnerable to chemicals than adults. In addition, they often put their hands into their mouths and play on surfaces treated with pyrethrin.

The EPA reports 6,000 cases of adverse reactions annually. Most reports are not confirmed, but many report symptoms, including vomiting, muscle aches, and peeling skin. A few people have even reported deaths. According to the EPA, pyrethroids may have caused at least 50 fatalities since 1998. But the EPA does not know whether or not the chemicals are linked to these deaths.

In addition to human allergic reactions, Pyrethrin is also dangerous to aquatic organisms and beneficial insects. In areas where ticks are common, federal law suggests that pyrethrin be used to control the population of insects that spread the disease. But despite the dangers, the federal government has recommended its use for preventing tick-borne illness, and this pesticide is still used to control mosquitoes.

Although pyrethrin is a powerful insecticide, it is only effective when used at lower concentrations, and in food preparation areas, it is not enough to kill the flies; they are simply driven away from the area before they die. The pyrethrins in food establishments have been effective in reducing the number of pests and disease-carrying mosquitoes. This makes it one of the most effective pesticides in the market.

However, pyrethroids are incredibly toxic to insects, causing motor dysfunction and paralysis. The pesticides also affect sodium channels, which cause cells to depolarize and block action potentials. This in turn causes tremors, clonic seizures, and motor coordination disorder.

Pyrethrins can be found in over two thousand registered pesticides. Many of these products are used on crops, lawns, and ornamental plants. Some are even used on livestock. Some are even approved for use in organic farming.