2022

These pesticides may increase cancer risk in children


Research by a team including Dr. Julia Heck and Dr. Beate Ritz links prenatal exposure to specific chemicals to higher rates of eye cancer.

Past research has shown that pesticide exposure increases the risk of cancer. Now, UCLA-led research has exposed which specific pesticides increase the risk of retinoblastoma — a rare eye tumor — in children.

The study, published in the August International Journal of Hygiene and Environmental Health, found that children prenatally exposed to the chemicals acephate and bromacil had an increased risk of developing unilateral retinoblastoma, or cancer in one eye, and that exposure to pymetrozine and kresoxim-methyl increased the risk of all types of retinoblastoma.

“What’s important is looking at specific bad actors and identifying them,” said Dr. Julia Heck, UCLA Fielding School of Public Health associate professor of epidemiology, and a co-author of the work who studies environmental causes of childhood cancers.

Identifying specific pesticides correlated with cancer is the first step toward banning or replacing them with less harmful options.

The researchers studied land use data and pesticide use reports — which provide information on where, when and in what quantity the chemicals are applied — to determine locations of possible pesticide exposure. They considered 132 pesticides that are associated with cancer.

They compared children with retinoblastoma to random children with California birth certificates and found that those with cancer were more likely to have been born in neighborhoods near applications of specific pesticides.

Pesticides can increase cancer risk by disrupting hormones, damaging DNA and causing inflammation. Children are especially vulnerable because their organs are still developing, according to previous research.

Childhood cancer is one of the leading causes of death in children, but unlike adult cancers, there are not as many identified causes.  Although retinoblastoma has high survival rates, children can suffer long-term effects from chemotherapy and radiation, Heck said, which is why it’s crucial to identify causes and prioritize prevention.

Other factors that increase the risk of retinoblastoma include air pollution, sunlight, X-rays and workplace hazards.

Industrywide, farmers should become more conscious about the potential health risks of pesticide applications and consider alternatives, said lead author Shiraya Thompson, who conducted research as a graduate student in epidemiology at the UCLA Fielding School of Public Health.

It’s also important to consider health inequities that may arise from different levels of exposure to pesticides, Thompson said. The team also includes Dr. Beate Ritz, UCLA Fielding School of Public Health professor of epidemiology and environmental health sciences, and colleagues from the University of Southern California and the University of North Texas.

Because it’s difficult for parents to protect themselves and their families against pesticide exposure, regulatory agencies such as the Environmental Protection Agency should limit the use of harmful pesticides to reduce cancer risks, Heck said.

“You might have very little control over what's going on in the cornfields near you,” she said. “And you might not even be aware of what farmers near you are putting down.”

Thompson stresses that future research, such as animal studies, are needed to reveal what pesticides are truly carcinogenic and what specific harms they cause.

Julia Heck
Julia Heck
Epidemiology
Read Faculty Profile
Dr. Beate Ritz
Beate Ritz
Environmental Health Sciences Epidemiology
Read Faculty Profile
Karin Michels
Karin B. Michels
Epidemiology
Read Faculty Profile
Dr. Shira Shafir
Shira Shafir
Community Health Sciences Epidemiology
Read Faculty Profile
Jian Li
Jian Li
Environmental Health Sciences Epidemiology
Read Faculty Profile
Alexandra Binder Headshot
Alexandra Binder
Epidemiology
Read Faculty Profile
Jonathan Jacobs
Jonathan Jacobs
Epidemiology
Read Faculty Profile
Roch Nianogo
Roch A. Nianogo
Epidemiology
Read Faculty Profile
sheena sullivan photo
Sheena G. Sullivan
Epidemiology
Read Faculty Profile
Dr. Anne Rimoin
Anne Rimoin
Epidemiology
Read Faculty Profile
Dr. Shane Que Hee
Shane Que Hee

Industrial Hygiene & Analytical Chemistry

Environmental Health Sciences
Read Faculty Profile
Headshot
Christie Jeon
Epidemiology
Read Faculty Profile
Marissa J. Seamans
Marissa Seamans
Epidemiology
Read Faculty Profile
Otoniel Martinez-Maza
Otoniel Martinez-Maza
Epidemiology
Read Faculty Profile
Hashibe, Mia
Mia Hashibe
Epidemiology
Read Faculty Profile
Pamina Gorbach
Pamina Gorbach
Epidemiology
Read Faculty Profile
Elizabeth Rose Mayeda photo
Elizabeth Rose Mayeda
Epidemiology
Read Faculty Profile
Curtis Eckhert
Curtis Eckhert
Environmental Health Sciences
Read Faculty Profile
Akihiro Nishi Headshot
Akihiro Nishi
Epidemiology
Read Faculty Profile
Rachael Jones
Rachael Jones
Environmental Health Sciences
Read Faculty Profile
Naomi Greene
Naomi Greene
Epidemiology
Read Faculty Profile
Faculty/staff profile placeholder image
Jørn Olsen
Epidemiology
Read Faculty Profile
Feng Gao
Feng Gao
Environmental Health Sciences
Read Faculty Profile
Faculty/staff profile placeholder image
Catherine Carpenter
Epidemiology
Read Faculty Profile
Dr. Candace Tsai
Candace Tsai

Associate Professor for Industrial Hygiene and Environmental Health Sciences

Environmental Health Sciences
Read Faculty Profile
Dr. Dvora Joseph Davey
Dvora Joseph Davey

Dr. Joseph Davey is an infectious disease epidemiologist with over 20 years' experience leading research on HIV/STI services for women and children.

Epidemiology
Read Faculty Profile
Su Yong Jung
Su Yon Jung
Epidemiology
Read Faculty Profile
Dr. Zuo-Feng Zhang
Zuo-Feng Zhang
Epidemiology
Read Faculty Profile
Dr. Robert Schiestl
Robert Schiestl
Environmental Health Sciences
Read Faculty Profile
Dr. Yifang Zhu
Yifang Zhu
Environmental Health Sciences
Read Faculty Profile
Ximena Vergara
Ximena Vergara
Epidemiology
Read Faculty Profile
Dr. Lara Cushing
Lara Cushing
Environmental Health Sciences
Read Faculty Profile
Faculty/staff profile placeholder image
Leeka I. Kheifets
Epidemiology
Read Faculty Profile
Dr. Oliver Hankinson
Oliver Hankinson

Dr. Hankinson is a Distinguished Professor of Pathology and Laboratory Medicine, and of EHS, and Chair of the Molecular Toxicology IDP

Environmental Health Sciences
Read Faculty Profile
Dr. Liwei Chen
Liwei Chen

Professor in Epidemiology

Epidemiology
Read Faculty Profile
DerSarkissian, Maral
Maral DerSarkissian
Epidemiology
Read Faculty Profile
Dr. Wendie Robbins
Wendie Robbins
Environmental Health Sciences
Read Faculty Profile
Richard Ambrose
Richard Ambrose
Environmental Health Sciences
Read Faculty Profile