PFAS Pollutants Found in Soil at Dov Airfield Also Detected in Potatoes Grown in Gaza Envelope Communities

They cause severe contamination of water wells, they are delaying development work at Dov Airfield after being found in the soil, and now, for the first time in Israel, they have been detected in agricultural produce: chemicals from the PFAS group, which are linked to a long list of health problems, were identified in potatoes sampled from fields in the Gaza envelope. Researchers believe they are carried by the wind to the fields after being released from explosives during the prolonged fighting. The study, conducted by a group of leading researchers from the Hebrew University, the Ministry of Health, the Volcani Institute and South R&D, and led by Nitzan Shay, Prof. Beni Hefetz, Dr. Shira Rosenzweig and Dr. Eviatar Ben Mordechai, examined for the first time how active warfare affects the spread of PFAS pollutants in agricultural systems adjacent to war zones. The researchers found the dangerous pollutants in all potato leaves sampled in the Gaza envelope and in the vast majority of potato tubers, though at lower concentrations.

Global regulation is still being formulated: in Europe and the United States, these pollutants are routinely monitored in eggs, fish and meat. In Israel there is no organized policy for sampling them, even though local regulation follows developments in Europe. PFAS are a family of tens of thousands of compounds containing especially strong carbon-fluorine bonds, which are highly resistant to breakdown in the environment and in the human body. Their properties cause them to accumulate in ecosystems and in people. Some of them, such as PFOA and PFOS, have been proven to cause cancer and other diseases. The main source of PFAS is everyday products, such as packaging, water-repellent products, Teflon-coated cookware, cosmetics and plastic products. PFAS is the active ingredient in several firefighting foams, making them especially common at airports, refineries, fuel storage tank farms and military bases. The use of these foams, in real events or training exercises, sends these pollutants into the environment, into soil and into water sources, and from there into the human body. Their spread in the environment is especially extensive after years of uncontrolled use. In Israel, 15% of drinking-water wells and 70% of water sources tested for agriculture contained residues of PFAS pollutants above the standard, leading to the closure of major water wells in the country. PFAS compounds were also found in all treated wastewater and sludge samples from wastewater treatment plants that were tested, similar to findings reported in Europe and the United States since the early 2000s. Since in Israel 50% of the water sources used for agriculture are based on treated wastewater and sludge is often used as organic fertilizer (compost), these data are especially concerning.

These chemicals, known as “forever chemicals” because of their persistence, withstand high temperatures and usually make up 1% to 3% of the total weight of an explosive. They are found in about 20% of common munitions manufactured in the United States. During an explosion, and in extreme heat, these substances are released into the atmosphere and carried in the air. The dominance of some of the compounds in plant foliage provides evidence that the contamination was absorbed from the air. The researchers analyzed potato samples collected from border-adjacent agricultural fields near the combat zones. The samples were collected from 34 fields in the Gaza envelope and from three fields in the Ra'anana area. According to the findings, potato leaves in the Gaza envelope contained PFAS concentrations of volatile, short-chain substances that were 10 times higher, mainly PFBA, which is not considered carcinogenic, though studies have linked exposure to thyroid disease, compared with the leaves tested in the Ra'anana area. In addition, the ratio between PFAS concentrations in the leaves and their concentrations in the soils sampled in the Gaza envelope was especially high, by hundreds of times.

These data indicate, for the first time, a possible link between the presence of these pollutants in plants and proximity to a war zone, even though no air samples were collected. The high concentrations measured in the leaves relative to the soil, together with the dominance of some of the compounds in the plant foliage, provide strong evidence that the main source of contamination in the leaves is direct uptake from the atmosphere following deposition of pollutants from the air, rather than uptake through the root system from the soil. Although the average concentration of PFBA in the potato tubers was lower than the concentration in the leaves and stood at 0.15 nanograms per gram, it is difficult to assess the safety threshold of the amount consumers are exposed to without additional toxicological research. Exposure to these pollutants is also likely in other food products, and at higher levels in leafy vegetables, where concentrations are expected to be higher.

Different PFAS compounds were found in all agricultural soils tested within up to 19 kilometers of the border. The total concentration in the soil itself was low, but it contained chemicals known to be carcinogenic, such as PFOS and PFOA. According to the researchers, these came from treated wastewater and compost used in the fields. Lower levels were found in the control soils in Ra'anana. "PFAS pollutants are not among the most studied chemical groups by chance," said Dr. Eviatar Ben Mordechai. "Exposure to them is extensive and comes from many sources in everyday life, from food packaging, cookware and clothing, through drinking water and food, and sometimes from the air. The combination of exceptional persistence, wide dispersion in the environment, widespread exposure and accumulation capacity requires special attention. As of today, the most effective way to deal with PFAS pollution is to reduce the use of products containing these substances and exposure to them."

Forever chemicals are repeatedly found in agricultural produce around the world, indicating the weakness of regulation. According to a March publication by the Environmental Working Group, about 40% of non-organic fruits and vegetables grown in California contain residues of PFAS. There is no definition in the European Union for maximum PFAS levels in plant-based agricultural produce, and the same is true in Israel. In Israel, like in most countries, there are no threshold values for exposure to PFAS pollutants in fruits and vegetables. While countries in Europe monitor the situation in the field, in Israel there are no routine tests for these pollutants in agricultural produce. The main regulation is through water reservoirs and soil: the Ministry of Health and the Water Authority close wells where PFAS contamination is detected, thereby reducing public exposure. Calcalist has learned that Bactochem, one of the leading laboratories in the field in Israel, is in advanced stages of accreditation to perform the test for food products, in order to provide a response for ongoing monitoring and enforcement in accordance with regulatory requirements. As part of the internal tests it carried out as part of adapting the method, PFAS residues were found in some of the products tested. The Ministry of Health says that in Israel, like in the European Union, maximum PFAS levels exist for several foods of animal origin, according to scientific knowledge and the current risk assessment. In the European Union there is no definition of maximum PFAS levels in plant produce, and the same is true in Israel. Accordingly, the focus worldwide today is on monitoring, data collection and exposure assessment for the purpose of shaping future policy, and not on rejecting agricultural produce based on regulatory values that do not exist.

In response, the Ministry of Health said: "The Ministry of Health conducted an initial survey to examine the presence of PFAS in vegetables, which included samples from agricultural fields and markets, alongside tests of treated wastewater and reservoirs. A comparison was carried out between crops irrigated with fresh water and crops irrigated with treated wastewater and floodwaters from areas where there is suspicion of PFAS contamination. These preliminary findings serve as an indication for continued examination of the issue. A summary report will be published on the Ministry of Health website."