Life should not be devalued to grow rice. Sometimes 13 pesticides are spat out in a breath.

Rice is a staple in many parts of Asia, with Malaysians consuming an average of 2.5 plates of rice a day. As Malaysia's basic food sources, the rice and rice industries are given special attention by the government and are important sources of income for the country. In order to increase rice yield, farmers often use pesticides, but at the same time, pesticide environmental pollution has become an inevitable and urgent problem to be solved.

Long-term exposure to pesticides will have serious adverse effects on health, such as acute and chronic neurotoxicity. At present, most of the workers who have been exposed to pesticides for a long time are farmers. They are exposed to pesticides by direct and indirect inhalation in the process of preparing (mixing and loading) and applying (spraying) pesticides, resulting in pesticide residues in the human body. In the process of human contact with pesticides, pesticides can be inhaled through the surface of the lungs and then infiltrated into other parts of the body through blood circulation, which can cause serious adverse effects on health after long-term exposure. Cancer, nerve damage, abnormal liver function, renal insufficiency and Parkinson's syndrome are all related. Lack of awareness of safe use of pesticides, lack of personal protective equipment and poor personal hygiene habits are three important reasons for farmers to be threatened by pesticides. The survey showed that only 8.4% of rice farmers used appropriate personal protective measures, and 91.6% did not wear any personal protective equipment.

The Hazwanee Hamsan team studied the concentration of commonly used pesticides in the exhaled air of rice farmers and whether this concentration posed a health threat to rice farmers. Eighty-three farmers from the village of Guala Selango in Tanjong Garland, Malaysia, took part in the study. The researchers collected the exhaled gas from each volunteer and analyzed the pesticide residues in the exhaled gas.

The results showed that pesticide residues were detected in 82 of 83 individual exhaled air samples (one of which failed to obtain sufficient samples due to accidental shutdown of the air pump during gas collection). Specifically, up to 13 pesticides were detected in the air exhaled by rice farmers. The frequency from high to low was tricyclazole, tebuconazole, chlorobenzamide, trimethoprim, oxime, difenoconazole, fipronil, prochlor, imidacloprid, imidacloprid, buprofezin, propiconazole and azoxystrobin. Among them, tricyclazole (the most commonly detected pesticide) and azoxystrobin (the least detected pesticide) are fungicides (fungicides are widely used in the vegetative growth, reproduction and maturation stage of rice, the aim is to minimize the occurrence of crop diseases and maintain the yield of agricultural products). Because farmers believe that tricyclazole is cheap and effective compared with azoxystrobin, most farmers in this area choose to use tricyclazole, which is one of the reasons why this pesticide has been detected the most times.

Table 1. Pesticide residues detected in the air exhaled by rice farmers.

The results also showed that a variety of pesticides could always be detected in individual exhaled gas samples. of all the pesticide residues detected, the average concentration of propachlor was the highest (107.19 ng/m3), while the average concentration of imidacloprid was the lowest (18.96 ng/m3). The maximum concentration of pesticide residues ranges from 47.80 ng/m3 (azoxystrobin) to 462.50 ng/m3 (fipronil).

The data obtained in this study are very useful for farmers' health risk management. We recommend that farmers be provided with appropriate training on the use of pesticides and the appropriate use of personal protective equipment to reduce farmers' exposure to pesticides.