JIST

Pesticide Poisonings in South East Asia: A Neglected Issue

Agriculture medicine is closely related to rural health and safety. It engages a multidisciplinary team of medical professionals, engineers, sociologists, epidemiologists, and psychologists, together with agricultural advisors and farmers. A particular aspect of agricultural medicine refers to the burden of disease linked to the poisonings and use of pesticides. Over 300,000 people die from pesticide poisoning annually, and pesticides are a main source of poisonings in some SEAR countries.1 Deliberate self-harm (DSH) with pesticides is a major public health problem in many developing countries of the world. Agriculture is the primary occupation of most people living in the country and pesticides are extensively used in agriculture. These agents are most frequently used in DSH. The most vulnerable groups consist of children, women, workers in the informal sector, and poor farmers, who are in most cases, debt driven. Maharashtra saw 4453 farmers’ suicides in 2006, over a quarter of the all-India total.2

 

Workplace-related poisonings are highly associated with the frequency of spraying, hazard level of pesticides used and skin contamination while spraying either through direct contact or wet clothing.3 Further, unsafe pesticide storage and disposal pose considerable risks of accidental poisonings in children and contaminate water and food supplies.

 

To treat poisonings, the South-East Asia Region has 17 functioning Poisons Information Centres with an installed capacity to respond to a maximum of 5000 cases, as well as a small regional professional pool of toxicology experts. Doing a lot with little, these experts have benefited from support from WHO and other agencies for capacity building in toxicology, use of harmonised data-collection systems, protocols and guidelines and lab equipment. To date, none of the existing poison centres works 24//7. While encouraging achievements are visible, a lot more needs to be done. Poor inadequate facilities remain a major challenge. For many toxicology labs, quality assurance and accreditation are not yet established. Lack of skilled personnel also leads to poor networking among poison centres.

 

The lack of attention to this issue has many causes. The data on poisoning cases is generally very poor and limited to hospital data. Because reporting a case of poisoning may have legal implications, victim’s relatives are often reluctant to give details of the incident. Poor evidence is a major hindrance in obtaining the needed attention of policy-and-decision-makers.

 

It is important to note that several recent reports4,5 have suggested that exposure to agricultural pesticides produces depression, and depression is a major risk factor for self-harm. This would imply that in some cases of self harm attempts, the victim’s behaviour is not completely deliberate but may be conditioned by chronic exposure to pesticides. The health sector urgently needs to develop and strengthen poisoning-prevention programmes, with a special focus on improving clinical services. For this purpose, together with UNEP, WHO prepared a training tool Sound Management of Pesticides and Diagnosis and Treatment of Pesticide Poisoning.6 Strengthening farmers’ education programmes on pest management systems that are more sustainable and less harmful to health is a priority.

 

Throughout the world, most pest control strategies that relied mainly on the use of chemicals repeatedly led to failure.7 In agriculture, frequent treatments disturb the agro-ecosystem balance by killing the natural enemies of pests. Populations of previously unimportant pests can increase when primary pests and natural enemies are destroyed. In both agriculture and public health, repeated applications have favoured the development of resistance as well as cross-resistance to pesticides, in pest and in vector populations.8

 

Increasing concern over effects of pesticides on health and the environment has led to public pressure to reduce their excessive use. For example, groundwater contamination and poisoned wells are a matter of grave concern in countries with intensive agriculture, and in some countries concern over pesticide residues in food is already changing consumption patterns.

 

Malaria and other vector-borne diseases are a major public health problem in our region. In the wake of increasing resistance to both drugs and pesticides, there is a need to establish integrated vector management strategies that are less reliant on chemical methods of disease control. These strategies should involve other sectors and local communities in managing the ecosystem to reduce health risks and increase the sustainability of programmes to control vector-borne diseases.

 

Alternative approaches that help reduce reliance on pesticides have been developed and tested in recent decades. As a result, Integrated Pest Management (IPM) and, to a lesser extent, Integrated Vector Management (IVM) are increasingly introduced and promoted in agriculture and as part of vector-borne disease control, respectively.

 

IPM is a knowledge-intensive and farmer-based management approach that encourages natural control of pest populations. All appropriate techniques are used such as enhancing natural enemies, planting pest-resistant crops, adapting cultural management, and, as a last resort, using pesticides judiciously.9

 

IVM is defined as a rational decision-making process for optimal use of resources for vector control. Its features include methods based on knowledge of factors influencing local vector biology, disease transmission and morbidity; use of a range of interventions, often in combination and synergistically; collaboration within the health sector and with public and private sectors that impact on vectors; engagement with local communities and other stakeholders; and a public health regulatory and legislative framework. Both IPM and IVM10 start from a thorough understanding of the local ecosystem and recognise that decision making needs to be decentralised to local levels and based on regular field observations and clear criteria. This implies a need for the development of decision-making skills and capacities for Primary Health Care personnel oriented towards rural occupational and environmental health.

 

A pilot project on integrated pest and vector management that started in Sri Lanka in 2002 (with UNEP, FAO and WHO support) has been unique in educating farmers about agriculture and public health by involving farmers in vector-management activities.11 An external evaluation carried out in 200612 reported that farmers now applied insecticide less frequently during rice production as a result of becoming more aware of adverse effects. Farmers also regularly conduct vector-control actions such as eliminating breeding sites, rearing larvivorous fish at household level, cleaning the domestic surroundings, applying mineral oil to bodies of water and covering water containers. A separate study of this pilot project13 reported a 60% increase in the use of bed nets, also attributable to the intervention, indicating there was an increased awareness about personal protection.

 

WHO, along with FAO and UNEP are committed to promoting integrated strategies for more sustainable pest and vector management with the ultimate objective to ensure the sound management of chemicals.

 

Pesticide poisonings pose a major threat to the health and safety of farmer communities in the Region. Public health and Agriculture need to join efforts and address this increasing problem in a more holistic and prevention oriented manner, beyond case management. A key policy change would be to phase out the most toxic chemicals, namely the WHO class I and II pesticides,14 and substitute these with less toxic groups of pesticides. The International Code of Conduct on the Distribution and Use of Pesticides15 should be used as reference to identify which measures need be taken to drastically reduce the risks of poisonings.

 

Establishing analytical toxicology facilities and capacity building opportunities are paramount in addressing this neglected problem, as are surveillance and data collection and national and regional networking.

 

 

Poisonings also depend on psychosocial and economic factors that need to be addressed, and hence, a multidisciplinary approach is called for that combines occupational health and safety, addressing mental health in communities, enhancing women’s health, and protecting children’s environmental health, for example. This would address the factors leading to poisonings and reduce the burden. Addressing the situation of illiteracy and debt entrapment common to many farmers in the Region is key to reducing the burden of disease related to pesticide use. Finally, and may be most importantly, measures leading to reduce reliance on pesticides, in particular IPVM (Integrated Pest and Vector Management), will reduce the load and availability of pesticides, but also reduce pollution from chemicals in general, and in the longer term, show significant health and environmental benefits.