Pesticides used in Thailand and toxic effects to human health

Abstract

Pesticide intoxication is one of the major public health problems in Thailand and it is caused by intensive use and exposure to pesticides. There was an increasing trend of pesticides imported from about 110,000 tons (14,000 million Baht) in 2007 to approximately 172,000 tons (24,000 million Baht) in 2013. Herbicides were the major pesticides with the highest proportion of import (62-79%) followed by insecticides (12-23%) and fungicides (5-11%). There were about 49,000 to 61,000 reported cases of pesticide intoxication each year with morbidity rate between 76.4 and 96.6 per 100,000 populations. The reported cases of the toxic effects of substances during 2007-2013 were found predominantly in the Central region of Thailand (31-36%), followed by the Northeastern region (27-31%), while the annual proportion of the North (18-20%) were almost equal to those of the South (18- 19%). The numbers of cases were usually increased during the growing season of many crops in rainy season (May-August) each year, and it was found mainly in farmers and farm workers. The highest risk was found in patients aged between 45 and 54 years, followed by the groups of 55-64 years and 35-44 years, while the poison risk in men was greater than women. Most of the pesticides identified from patients were organophosphates, carbamates and herbicides, whereas approximately 85-90% of total cases could not be identified the causing pesticides. In conclusion, a large amount of pesticides have been annually imported into Thailand and the intensive use of pesticides certainly has consequences for human health and environments even though identifying the true extent of these is quite difficult. To reduce the intensive use of pesticides, it is an urgent need to promote the organic farming practices and search for the effective biopesticides or biological agents to control agricultural pests in order to replace the chemical pesticides.