Veterinary drugs tied to obesity

Fudan University research shows negative effects on children who ingest antibiotics

Veterinary antibiotics ingested by humans in the form of tainted food and drinking water have been linked to childhood obesity by researchers at Shanghai-based Fudan University.

The discovery, recently published in the United States scientific journal Environment International in the United States, came as a result of five years of study by a team working at the university's Education Ministry-designated public health security laboratory and its College of Public Health.

First, the team collected 1,500 samples of children's urine and used these to develop a method of screening that would identify the presence of 21 kinds of antibiotics.

This method was then applied to 586 urine samples collected from children aged 8 to 11 in Shanghai, nearly 80 percent of the samples contained traces of the drugs.

To assess the relationship between antibiotics and obesity, researchers divided the children into three groups according to the concentration of residues of veterinary antibiotics detected in their urine.

According to the report, a "positive correlation" was found between the concentration of veterinary antibiotics ingested and the incidence of childhood obesity.

"In the high concentration group, the incidence of overweight and obese children was three times that of the low concentration group, and in the medium concentration group the incidence was almost double that of the lowest group," it said.

Wang Hexing, one of the team's lead researchers, said scientists across the globe had for some time proposed a link between the use of antibiotics during infancy and early childhood and obesity.

Yet those studies were largely confined to medicines indicated for use in humans, whereas Wang and his team focused on antibiotics used by veterinarians.

"We believe that the veterinary antibiotics mainly enter the human body through contaminated water and food," he said.

According to Wang, the amount of antibiotics used in China reached 162,000 tons in 2013, accounting for roughly half of global consumption. Around 52 percent is used for veterinary purposes and more than 50,000 tons are discharged into the environment through the soil and water, he said.

Sun Guogen, an information officer at Fudan University's College of Public Health, reiterated that the research found no association between obesity and the antibiotics designed for human use.

"We didn't find in our research that obesity is associated with medical antibiotics used for humans. Such antibiotics may enter the human body in high doses in the short term but are easily and quickly metabolized. However, those that come from food and drinking water may be at a low dose but can accumulate in the long run," said Sun.

zhouwenting@chinadaily.com.cn