The risk of children with autism is caused by their mother's exposure to pesticides during pregnancy

(pregnant women) - Pregnant women who live near fields and farms that use pesticides are at a higher risk of having a child with autism spectrum disorder or developmental delay, a The study was conducted by scientists at UC Davis MIND Research Institute. The linkage is stronger when exposure occurs during the second and third trimesters of pregnancy.

Many studies in California have examined the link between specific classes of pesticides, including organophospates, pyrethroids and carbamates, used during pregnancy by study participants. to diagnose autism and slow development in the children of these women. This study was presented online on Environmental Health Perspectives.

'This study confirms previous research findings on the association between autistic childbirth and maternal prenatal exposure to California industrial chemicals' , the study's lead author. , Janie F.Shelton, a graduate student at UC University, who is now consulting with the United Nations. 'While we still need to study why some women's groups are more vulnerable to exposure to these chemicals than others, a very clear message is that women Pregnancy should be given special care to minimize, avoid contact with agricultural chemicals '.

California is the leading agricultural production state in the United States, revenues from agricultural crops reached 38 billion dollars in 2010. In this state, about 200 million pounds of active pesticides are used every year. most in areas like the Central Valley, north to Sacramento Valley and south to the Imperial Valley on the California - Mexico border. While pesticides are important to modern agriculture, some of the pesticides commonly used are neurotoxic substances and may pose a threat to fetal brain development. Infants in the womb, potentially leading to growth retardation or autism.

This study was conducted by examining the use of commercial pesticides based on reports of California Pesticide Use Report and linking data to the address living of 1,000 study participants in the study called The Risk of Childhood Autism due to Northern California's (Northern California-based Childhood Risk of Autism from Genetics and the Environment (CHARGE) Study). The study included households with children 2 to 5 years of age who were diagnosed with death or developmental delay or with normal development. The research was led by Irva Hertz-Picciotto, a researcher at MIND Research Institute, a professor and vice president of the Department of Public Health Science at UC Davis University. Most study participants live in the Sacramento Valley area, Central Valley and San Francisco Bay area.

21 chemical compounds have been identified as organic phosphorus, including: chlorpyrifos, acephate and diazinon. The pyrethroid insecticide is the second most commonly used pesticide, 1/4 of which is esfenvalerate, followed by lambda - cyhalothrin permethrin, cypermethrin and tau-fluvalinate. 80% carbamate is methomyl and carbaryl.

In this study, researchers used questionnaires to obtain information on the whereabouts of study participants during the pre-conception and pregnancy stages. Later, these addresses were updated on the map along with the locations where the agricultural chemicals were used based on pesticide use reports to identify areas near the population. The study also identifies who has been exposed to any agrochemicals.

'We map the place to live during pregnancy and around the time of birth. In California, pesticide users have to report where, what pesticides are being used, how much to use when used, ' Hertz-Picciotto said. ' What we see is that some classes of pesticides are often used near the residence of women who have children with autism or who are slow to recognize, or other retarded skills'.

Researchers found that during the study period about one-third of participants in the CHARGE Study study lived close to - within 1.25 to 1.75km - pesticide-using areas trade. Researchers have found that some of the links are stronger among women living near pesticide-using areas.

Exposure to organic phosphorus during pregnancy is associated with a high risk of having a child with autism, especially contact with chlorpyrifos during the second trimester . Pyrethroids are associated with autism spectrum disorder just before conception and during the mother's last trimester. Exposure to carbamate during pregnancy is related to the child's developmental delay.

Exposure to insecticides for people living near agricultural production areas can be a health problem, especially during pregnancy, because while in the womb, fetal brain is growing and can be much more vulnerable than an adult's brain. Because these pesticides are neurotoxic, fetal exposure to chemicals in the early development process may distort the process of developing structures and signaling neurons. , leading to changes in stimulation and inhibition of mechanisms that govern mood, ability to learn, socialize, and behavior.

"In the early stages of pregnancy, the fetal brain is developing synapses, the distance between nerve cells, in which electrical impulses are turned into neurotransmitters that jump off a neuron. another neuron to transmit messages The formation of neural joints is very important and this may also be where the insecticides activate and affect neurotransmitters' , Hertz- Picciotto said.

The CHARGE Study study emphasized the importance of maternal nutrition during pregnancy, especially the use of prenatal vitamins to reduce the risk of autistic childbirth. While it is impossible to completely eliminate the risks of environmental exposure, Hertz-Picciotto said it is important to find ways to reduce exposure to chemical pesticides, especially to children. .

'We need to open dialogues to find out how to do this at both the social and personal levels,' she said. 'If it was my family, I would not want to live close to areas that use a lot of pesticides'.