Agriculture & Veterinary Chemicals Residue, Human Health and Bangladesh
Agriculture and Veterinary (AgVet) chemicals are broadly used to protect crops, livestock, and other animals and plants from pests and diseases. AgVet chemicals include pesticides (eg. insecticide, herbicide, fungicide and rodenticide) , and veterinary medicines (eg. hormones, and antibiotics). They are also used to boost plant and animal production. For example, pesticides increase crop production through killing of pest’s plants and animals. Drugs such as hormones and antibiotics help to boost animal growth.
Though, the use of AgVet chemicals provides many benefits, however, it is believed that there is also some risk that residues of these chemicals may be found in agricultural produce. Residue are remains of a chemical either the chemicals itself or as breakdown products. Residues in food and agriculture produce may result from the application of AgVet chemicals, accidental contamination or intentional treatment of animals or feed with chemical or drug or from environmental contamination.
AgVet chemicals residue may enter into the human body through food chains. Therefore, the risk of AgVet chemicals to human are in the risk of residues remaining on the food consumed. For example, if animals are fed on feedstuffs treated with pesticides, these hazardous chemicals can be taken up in meat, milk and milk products. This is mainly due to hydrophobic (fat loving) nature of some of pesticides that may cause them to be incorporated and accumulated in the tissues of living organisms. AgVet chemicals as residue if consumed by humans more than the recommended maximum residue limits (MRL) can be hazardous to humans.
Human health effects from pesticides residue in food include cancer, infertility, miscarriage, male sterility, birth defects, and effects on nervous system. The other pesticides related effects are disruption of endocrine system, and suppression of immune systems. Eating meat with unacceptable levels of hormones can lead to many side effects such as breast enlargement and ovarian cysts. Presence of antibiotics residues in milk can make people more vulnerable to allergic reactions to some medicines.
From recent survey of Australia’s agriproducts undertaken under National Residue Survey (NRS) and Food Standards Australia and New Zealand (FSANZ) show a high rate of compliance with food standards. For example, the National Residue Survey (NRS 2005) conducted during 2003-2004 found that 99% agriculture produce contains AgVet chemicals which are below the MRL s that is legally permitted or recognised as acceptable in or on a food. The survey results suggest that Australian produce are clean and are of high quality. The Survey included meat, grain, horticulture, and wild caught fisheries products (see Table 1)
Table 1 : Summary Results of Australian National Residue Survey on Agriculture Produce (NRS 2004)
AGRICUTURE PRODUCTS TESTED
NUMBER OF SAMPLES THAT EXCEEDED AUSTRALIAN STANDARDS or MRL
PERCENT OF SAMPLES THAT EXCEEDED MRL
Meat Products (cattle, sheep, pig, goat, horse and others)
7 samples out of 12654 samples tested
0 sample out of 1293 samples tested
Grain products (cereal grains, flour and bran, pulses, canola and others )
9 out of 5241 samples tested
Horticulture products (apple and pear, nuts, onion and others)
1 sample out of 571 samples tested
Fisheries-wild caught (coral trout, eel, mackerel, pink snapper, prawn, scallop, tuna, whiting)
0 out of 133 samples tested
Aquaculture products (barramundi, eel, marron, red claw, yabby, yellowtail kingfish)
1 out of 13 samples tested
The exposure of AgVet chemicals to humans (eg. pesticides) can be reduced through washing of all fruits and vegetables with large amount of tap water, peeling vegetables (eg. apple, pears, potatoes, carrots), removing the outer layer of leaves (eg. lettuce, cabbage), and trimming fat from beef, poultry, and fish (note : many chemicals such as high risk pesticides are fat soluble).
A regular chemicals residue monitoring program of Bangladesh agri-produce (eg. rice, fish, prawn, vegetable and fruit) would help to protect the health of the people of Bangladesh and to produce high quality food for domestic and export markets. Monitoring for residues further helps to audit the use of currently registered AgVet chemicals and whether chemicals are used according to good agriculture practice. Furthermore, monitoring of surface and groundwater for high risk pesticides residues and comparing the results with guideline reference thresholds values would help to avoid environmental consequences in Bangladesh; this program would also ensure beneficial uses of water for a number of purposes including irrigation, drinking, recreation, stock and domestic supply and aquaculture.
Kennedy, I.R., Skerritt, J.H., Johnson, G.I. and Highley, I. E. (1998). Seeking agriculture produce free of pesticide residues. Australian Council for International Agriculture Research (ACIAR, ACIAR Proceedings No 85. 406p.
NRS (2004). National Residue Survey Annual Report 2003-2004. Australian Government Department of Agriculture, Fisheries and Forestry, Canberra. 164p
WHO (1997).Guidelines for predicting dietary intake of pesticides residues. Geneva; Joint UNEP/FAO/WHO food contamination monitoring programme in collaboration with the codex committee on pesticides residues, Geneva,.
Wilson,J.S and Otsuki, T. (2004). To spray or not to spray: pesticides, banana exports, and food safety. Food Policy 29 : 131-146
The information was compiled by Dr Golam Kibria, Ph.D in September 2005 for http://www.sydneybashi-bangla.com/ . Views expressed in this article are those of the author and are not to be taken to be the views of any others including third parties. The author disclaims any liability for any error, loss or other consequences which may arise from relying on any information in this article. Dr Golam Kibria is a Senior Environmental Scientist with the Australia’s largest Rural Water Authority and based in Victoria