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Incidence of acute pesticide poisonings in Nicaragua: a public health concern M Corriols, J Marín, J Berroteran, L M Lozano and I Lundberg Occup. Environ. Med. 2009;66;205-210; originally published online 21 Nov 2008; doi:10.1136/oem.2008.040840
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Original article
Incidence of acute pesticide poisonings in Nicaragua: a public health concern M Corriols,1 J Marı´n,2 J Berroteran,2 L M Lozano,2 I Lundberg3 1
Karolinska lnstitutet, Stockholm, Sweden; 2 Ministry of Health, Managua, Nicaragua; 3 Uppsala University, Uppsala, Sweden Correspondence to: Marianela Corriols, CISTA/UNAN Leon, Campus Medico, Leon, Nicaragua;
[email protected] Accepted 26 September 2008 Published Online First 9 December 2008
ABSTRACT Objectives: To estimate the cumulative incidence rate of acute pesticide poisoning in the year 2000 among Nicaraguan subjects over 15 years of age. Methods: Data on pesticide exposure and health effects were assessed in a nationally representative survey. Based on self-reported cases, we estimated the 1-year incidence rate and the number of expected cases of acute pesticide poisonings in Nicaragua. Results: Among the 3169 survey respondents, we identified 72 persons who self-reported one episode of acute pesticide poisoning in 2000. Of these, 65 cases (90%) were related to occupational exposure, five (7%) to domestic exposure and two (3%) to intentional exposure. The cumulative incidence rate/100 individuals of pesticide poisonings in Nicaragua in 2000 was 2.3 (95% CI 1.7 to 2.8). This corresponds to 66 113 cases (95% CI 51 017 to 81 210). The highest rate was found among males in rural areas, particularly among farmers and agricultural workers. Conclusion: This study demonstrates an extremely high risk of acute pesticide poisoning in Nicaragua. Considering this, comprehensive measures should be implemented to reduce adverse health effects.
Pesticides are chemical substances used worldwide for the control of pests. While their benefits are well known, knowledge of the adverse effects of pesticide exposure on human health used to be limited.1 2 Today, however, the literature on the health effects resulting from exposure to pesticides is increasing rapidly.3 4 Adverse health effects are more common in less developed countries because of weak regulation, the low hazard awareness of users, inadequate use of personal protective equipment, lack of proper care during application and the use of highly toxic pesticides. Accidental and intentional poisonings have been more fully studied than occupational exposures through the use of reports from hospitals and toxicological centres.5–9 In developing countries, reported occupational and non-intentional cases vary from 10% to 50% as a percentage of total poisonings.10 In Nicaragua, as in other developing countries, the incidence of acute pesticide poisonings is unknown.11 12 About 7.5% of agricultural workers in Sri Lanka and 7.3% in Malaysia13 were estimated to have been intoxicated in a single year. The corresponding figures for Costa Rica14 and Brazil15 are 4.5% and 2.2%, respectively. The differences in estimates may partly be due to different definitions of poisonings. Self-reporting of cases is commonly used to estimate the incidence of acute pesticide poisonings Occup Environ Med 2009;66:205–210. doi:10.1136/oem.2008.040840
in agricultural settings. For instance, 25% of agricultural workers in Nicaragua16 and 31% of farmers in Vietnam17 reported one episode compatible with acute pesticide poisoning over a single year. In Indonesia, 21% of pesticide spraying operations resulted in three or more neurobehavioral, respiratory and intestinal signs or symptoms.18 In the United States, 7% of the studied cohort of licensed restricted-use pesticide applicators for whom health care visit data were available19 reported one or more pesticide-related health care visits. Only a small proportion of those affected sought medical care, suggesting that pesticide poisoning surveillance data may seriously under-report the frequency of such events.20 Even when active epidemiological surveillance is implemented, the figures registered are much lower than estimates based on self-reports.21 22 In more developed surveillance systems, as in California, available data still do not take into account those who having become ill after exposure did not visit a physician or call a poison centre, or cases of non-agricultural occupational exposures.23 We have found no studies that analysed the incidence of pesticide poisoning among the general population (including non-medically treated pesticide poisonings) in Central America and other developing countries. Official figures only report cases that received medical care at health facilities. After years of institutional strengthening of the surveillance systems, only 7000 cases were reported in the Central American region in 2000,24 which according to the Pan American Health Organization (PAHO) only represents between 1% and 20% of expected cases.25 In Nicaragua, officially reported cases of acute pesticide poisonings increased from 322 in 199026 to 1651 in 2000.27 Although the reported figure in 2000 was five times larger than that reported in 1990, a study based on a national self-report survey demonstrated that the official figures of acute pesticide poisonings in Nicaragua in 2000 represented less than 5% of all cases that sought medical attention.28 Using data from the same self-report survey, the main aim of this paper is to estimate the true number of acute pesticide poisonings in Nicaragua in 2000.
METHODS Ethics committee approval The Nicaraguan National Autonomous University Bioethical Committee in Leon, Nicaragua, reviewed and approved the research protocol. 205
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Original article Study area and population
Exposure and self-report case definition
In cooperation with the Nicaraguan National Institute of Statistics and Census, we collected a representative multistage sample of the entire Nicaraguan population aged 15 years and older. In the first stage, a random sample was drawn from each of the 17 national departments. The sample size for each department corresponded to the proportion of the national population living in that department. In the second stage, each department was divided into census segments and random samples chosen as in the first step. In the third step, homes were selected randomly within each segment as in the preceding steps. An individual who met inclusion criteria (age, ability to answer the questionnaire) was selected in each house from the group of eligible household members present when visited. We planned interviews with 3430 individuals and completed 3169, representing 92% of selected individuals. Part of the South Atlantic region (less than 4% of the national population) did not participate in the survey due to adverse weather conditions.
Exposure and health effects (signs, symptoms and acute pesticide poisonings) were self-reported. The participants were specifically asked if they were exposed to pesticides in 2000, if they had suffered signs and symptoms after pesticide exposure in 2000 and if they considered themselves to have experienced an acute pesticide poisoning event during 2000. Acute pesticide exposure was defined as contact between a pesticide agent and a person occurring over a short time period, generally less than a day. For this study, a self-reported case of acute pesticide poisoning was defined as a person who considered himself or herself to have suffered an acute pesticide poisoning event in 2000 as a consequence of a reported acute exposure to one or more pesticides at any dose and by any route (dermatological, respiratory, digestive or other), who developed any clinical manifestation of poisoning related to the reported pesticide in the first 24 h after the exposure. An acute pesticide poisoning case was self-reported but was confirmed by the researchers. Each self-reported case had to provide a plausible description of pesticide exposure that had occurred in the 24 h immediately preceding the reported health effect. These reported effects were reviewed by toxicologists who established the relationship between them and the pesticide reported. The presence of a known toxic syndrome or at least three symptoms or one physical sign compatible with the reported pesticide exposure was considered as an acute pesticide poisoning case.
Interview questionnaire A questionnaire designed to reveal pesticide exposure and its acute health effects was validated in a pilot survey29 performed in a sample of 600 inhabitants from rural and urban areas of Nicaragua. The questionnaire was adjusted following the pilot survey. We confirmed that the questionnaire’s questions were clearly understood by respondents and that we were obtaining appropriate information regarding pesticide exposure and health effects. Detailed information was collected on socio-demographic characteristics (sex, age, area of residence, occupation, income, level of education, employment and occupation), exposure assessment in the year 2000 (pest control activities, pesticide contact, frequency and duration of pesticide exposure, previous training, use of personal protective equipment, unsafe pesticide handling and application practices), health effects (presence of signs and symptoms in 2000, knowledge of the definition of acute pesticide poisoning, self-reported pesticide poisoning in lifetime and in 2000, name of pesticide causing the acute poisoning, activity related to acute pesticide poisoning, type of attention received), health and economic consequences (number of days lost because of disability, cost of health care). Symptoms related to cholinesterase inhibiting pesticides, pyrethrins, herbicides, fumigants and other pesticide exposure were included in the questionnaire. These symptoms were: headache, blurred vision, salivation, dizziness, nausea, vomiting, dyspnoea, muscle cramps (tremor and muscle twitching), asthma, fatigue, itchiness, skin lesions (irritation, rash, erosion, blistering), nail lesions (damage, lost), eye injures, lack of concentration, muscle weakness and depression. The respondent also could report any other symptom that they had experienced even though it was not listed.
Data collection The gathering of data was carried out carefully by a trained group of health personnel under the close supervision of the research team. Local health workers responsible for the Pesticide Control Program administered by the Ministry of Health were trained as interviewers by the research team. The interviews took place in the interviewees’ homes. The participants were informed about the purpose of the study and gave verbal consent to participation. A field supervisor reviewed the quality of the data gathered and entered them in a database for analysis. The data were collected during November 2001. 206
Data analysis Specific information was obtained about the cases who selfreported poisoning. The self-reported cases were analysed by sex, age, occupation, area of residence, type of exposure, type of poisoning, specific pesticide and severity. The cases were also classified as intentional (intending suicide) and non-intentional (occupational and accidental). We used the WHO poisoning severity score30 that classifies cases by severity of symptoms, the number of work days lost due to illness and the location where health care was received (no attention, self-medication at home, health centre and hospital). This allowed us to relate the clinical manifestations of poisonings with the therapeutic behaviour of patients and their families and the impact on workers’ productivity. The 1-year cumulative incidence rates in the entire cohort and in different subgroups (age, sex, occupation, area of residence, educational level and type of poisoning) were calculated. Based on estimated figures of the Nicaraguan population in 2000,31 we applied these specific rates to calculate the number of individuals in each subgroup and in the entire population who had experienced an episode of acute pesticide poisoning. The 95% confidence limits for these estimations were determined. The data analysis was carried out using SPSS v 13.
RESULTS Study population Of the 3430 persons selected in the countrywide sample, 3169 (1646 females and 1523 males) completed the questionnaire and were interviewed. Their average age was 39 years (range 15– 98 years), 1866 (59%) were urban residents and 1303 (41%) rural residents. Regarding occupation, 1236 (39%) participants were housewives, 697 (22%) were farmers, agricultural or cattle workers, 254 (8%) were students, 127 (4%) were technicians, and 95 (3%) were professionals. Other occupations accounted for the remaining 761 (24%) participants. One third of the Occup Environ Med 2009;66:205–210. doi:10.1136/oem.2008.040840
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Original article sample had completed primary education (6 years). Illiteracy was reported for 339 (26%) rural respondents and 187 (10%) urban respondents.
Pesticide exposure Summary figures for pesticide exposure are presented in table 1. Overall, exposure was more common among males, farmers, agricultural and cattle workers, and rural respondents. Domestic pest control, spraying crops and cattle treatment were the activities most frequent related to exposure. The pesticides most commonly used by the 697 farmers, agricultural and cattle workers were methamidophos (25%), paraquat (11%), chlorpyrifos (10%), deltamethrin (6%), cypermetrin (5%), malathion (4%), methomyl (3%), terbufos (2%), and methyl parathion, mancozeb and carbofuran (1% each). One person may have used only one pesticide or may have had a combined exposure to two or more pesticides. The percentages mentioned above refer to the most frequent pesticide reported. The known risk factors for pesticide poisoning were most frequently reported by farmers, agricultural and cattle workers: 89% did not have access to personal protective equipment, 75% did not have previous training in pesticide use, 48% had mixed pesticides, 39% had experienced a leakage while using a backpack sprayer, 38% had entered recently sprayed fields, 31% had stored pesticides at home, 27% had refilled containers, 25% had cleaned the pump nozzle by mouth, 10% had eaten and smoked after spraying without washing their hands and 3% had used empty pesticide containers for domestic purposes (storage of water and food, cooking). Differences in the proportions belonging to different subgroups between the sample and the national population were two percentage points at most.
Self-reported health effects The frequency of clinical manifestations in the first 24 h after pesticide exposure was very high: 62% of those exposed to pesticides (1666 respondents) reported they had experienced at least one of the symptoms or signs listed in the questionnaire, with cholinesterase inhibition related symptoms and skin lesions being the most frequently mentioned. Report of symptoms and signs without previous exposure was not considered to be a poisoning. Only 4% of the respondents Table 1 Characteristics of the population sample and pesticide exposure in Nicaragua in 2000 Sample, n (%) Sex Male Female Residence Urban Rural Occupation Housewives Farmers and agricultural workers Other occupations Education Primary education not completed Primary education completed Total
Exposed, n (%)
1523 (48) 1646 (52)
925 (61) 741 (45)
1866 (59) 1303 (41)
935 (50) 731 (56)
1236 (39) 697 (22)
518 (42) 560 (80)
1236 (39)
588 (35)
2088 (66) 1081 (34) 3169 (100)
1092 (52) 574 (53) 1666 (53)
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who reported signs and symptoms thought they had been poisoned. Considering that the key question defining a poisoning asked if the respondent considered they had experienced an episode of acute pesticide poisoning in the previous year, we also asked the respondents what they considered to be acute pesticide poisoning. Only one third of the respondents thought minor cases (according to the WHO definition), with few and nonsystemic symptoms, to be poisoning. We identified 72 people (2.3%) in our sample who had suffered an acute pesticide poisoning event according to our definition during 2000: 65 cases were related to occupational exposure, five to domestic exposure and two to intentional exposure. Sixty six cases (92%) were caused by a single pesticide and six cases (8%) by a combination of two or three pesticides (five cases with two pesticides and one case with three pesticides). As seen in table 2, most of cases were caused by cholinesterase inhibiting pesticides, followed by pyrethrins and fumigants. Forty seven of the 72 self-reported cases of poisoning were caused by 10 highly toxic pesticides recommended for banning or restricted use in Central America: methamidophos (19), methomyl (seven), aluminium phosphide (seven), chlorpyrifos (five), paraquat (three), methyl parathion (two), carbofuran (one), endosulfan (one), monocrotophos (one) and terbufos (one). Malathion, deltamethrin, cypermethrin, propoxur, copper oxychloride, temephos, terbuthylazine, 2,4-D, dichlorvos and brodifacoum caused the remaining reported cases. Using the WHO poisoning severity classification, 52 cases were classified as minor, 10 as moderate and 10 as severe. As seen in table 3, the cases classified as minor generally did not seek health care and lost less than 2 days of productive work. Moderate cases always attended health facilities (public and private health centres and hospitals) and lost between 3 and 7 days of work. The severe cases always attended hospital and lost more than 8 days of work. No individuals reported having suffered more than one acute pesticide poisoning in the studied year. However, 243 persons reported having experienced an acute pesticide poisoning at least once during their lives.
Estimation of the number of acute pesticide poisonings in Nicaragua Based on the 72 self-reported cases, we estimated the 1-year cumulative incidence of acute pesticide poisoning in the country and by sex, area of residence, education, occupation and type of poisoning. As seen in table 4, the 1-year cumulative incidence rate/100 individuals of pesticide poisonings in Nicaragua in 2000 was 2.3 (95% CI 1.7 to 2.8). This corresponds to 66 113 estimated cases (95% CI 51 017 to 81 210). The 1-year cumulative incidence rate/100 individuals was higher in males (3.9) than in females (0.8), in rural residents (3.5) than in urban dwellers (1.4), among farmers, agricultural and cattle workers (6.7) than among those in other occupations (1.0) and among less educated persons (2.8) compared to those with more education (1.2). We estimated that 59 686 cases (45 325–74 046) were occupational, 4591 (570–8612) were domestic accidents and 1836 (0–4381) were intentional. Applying the severity score, we estimated that 47 749 cases (34 877–60 620) were minor, 9182 (3500–14 865) were moderate and 9182 were severe (3500– 14 865). 207
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Original article Table 2 Self-reported signs and symptoms associated with self-reported cases Number of self-reported cases, n (%)
Chemical group
Pesticides name
Cholinesterase inhibiting pesticides
Pyrethrins
Organophosphates: methamidophos, malathion, chlorpyrifos, propoxur, methyl parathion, monocrotophos, terbufos, temephos Carbamate insecticides: methomyl, carbofuran, dichlorvos Cypermethrin, deltamethrin
Herbicides
Paraquat
3 (4)
2,4-D
1 (1)
Terbuthylazine Aluminium phosphide Endosulfan Brodifacoum Copper oxychloride Combination of pesticides Unknown pesticide
1 7 1 1 2 6 5
Fumigants Other pesticides
Other circumstances
39 (54)
13 (18) 7 (10)
(1) (10) (1) (1) (3) (8) (7)
Signs and symptoms Headache, blurred vision, salivation, dizziness, nausea, vomiting, dyspnoea, muscle spasm (tremor and muscle twitching), skin lesions, (rash, erosion, blistering), eye irritation, weakness, lack of concentration, depression Asthma, dyspnoea, fatigue, weakness, headache, nausea and vomiting Skin lesions (irritation, rash, erosion, blistering), nail damage, eye irritation Dyspnoea, eye, skin and respiratory mucosal irritation, muscle spasm, tremor Respiratory, mucosal, eye and skin irritation Dyspnoea, headache, nausea, vomiting, depression Headache, dizziness, nausea, seizures Bleeding, fatigue, dyspnoea Headache, respiratory irritation, eye and skin irritation Cholinesterase inhibiting pesticide symptoms Cholinesterase inhibiting pesticide symptoms
The number of cases exceeds 72 because of multiple exposures and unknown pesticides.
DISCUSSION The study demonstrated that exposure to highly toxic pesticides is widespread in Nicaragua, especially among farmers, agricultural and cattle workers despite international recommendations.32 33 Inadequate precautions when using metamidophos, aluminium phosphide, paraquat, methomyl and clorpyriphos, which are restricted pesticides in Central America,34 35 were the main causes of acute pesticide poisonings. We estimated there are approximately 66 000 cases of acute pesticide poisoning annually, 90% of which are related to occupational exposure.
Methodological considerations This study was designed as a retrospective survey that explored pesticide exposure and the effects of that exposure on the population in the year before the survey. As subjects had to remember events that occurred 12–23 months previously, a memory bias is possible and is one of the weaknesses of this study. Each exposed participant provided a detailed description of the exposure and its effects; few could not recall the name of the pesticide involved. Pesticide exposure is so frequent among the Nicaraguan population that people easily characterised their exposure and remembered the specific pesticide they applied in the months before the survey. The sampling technique allowed us to obtain a representative sample of the whole country. Random sampling techniques ensured that there was very limited selection bias and had many advantages including convenience, economy and efficiency. The questionnaire was validated in a pilot survey. The non-response
rate was low. The interviews were carried out by a trained group of technicians who were instructed not to influence respondents’ answers. No benefits were involved in reporting poisoning. The main concern regarding validity was the use of selfreported data that could have underestimated or overestimated the incidence of toxic effects. However, the consistency of reported exposure history, self-reported effects, days lost and out of pocket costs suggests poisonings were recalled accurately, especially the moderate and severe cases. Some of the reported cholinergic symptoms could have been caused by other factors such as heat stroke, while dermatological signs could also have been caused by trauma or infectious disease. Thus there is a possibility of over-reporting of symptoms. On the other hand, it is possible that some symptoms actually due to pesticides may have been attributed to heat stroke and not reported to the interviewers. Even though 62% of exposed respondents reported they had experienced at least one sign or symptom after pesticide exposure, only 4% of them considered that they were poisoned after the pesticide exposure. Thus, the likelihood of minor cases being reported was lower than for moderate or severe cases. Therefore, our results probably underestimate the number of less severe cases. Our results are unlikely to overestimate the number of mild, moderate or severe cases. All self-reported cases were checked to confirm that they met the criteria for our case definition. Each case was carefully reviewed to ensure that the reported effects were in accordance with the signs and symptoms linked to the poisoning agent. All 72 self-reported
Table 3 Self-reported cases of acute pesticide poisonings by WHO severity score, number of day lost and level of medical treatment
Score
Description
1 (minor)
Mild, transient and spontaneously resolving signs or symptoms Pronounced or prolonged symptoms or signs Severe or life threatening symptoms or signs
2 (moderate) 3 (severe) Total
Number of work days lost
Medical treatment
Self-reported cases, n (%)
,2
No medication, self-medication, health centre
52 (72%)*
3–7 .8
Health centre, hospital Hospital
10 (14%) 10 (14%) 72 (100%)
*Only two of 52 cases classified as minor received medical treatment at health units.
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Original article Table 4 Expected cases of acute pesticide poisonings in Nicaragua in 2000
n Sex Female Male Residence Urban Rural Occupation Farmers, agricultural and cattle workers Other Education ,7 years >7 years
Number of respondents
Number of selfreported cases
Incidence of APP/ 100 individuals (95% CI)
National population .15 years old in 2000
Number of expected APP cases (95% CI)
3169
72
2.3 (1.7 to 2.8)
2 909 911
66 113 (51 017 to 81 210)
1646 1523
13 59
0.79 (0.36 to 1.2) 3.9 (2.9 to 4.8)
1 485 850 1 424 061
11 735 (5381 to 18 089) 55 167 (41 366 to 68 969)
1866 1303
26 46
1.4 (0.86 to 1.9) 3.5 (2.5 to 4.5)
1 600 451 1 309 460
22 300 (13 788 to 30 812) 46 228 (33 107 to 59 349)
697
47
6.7 (4.9 to 8.6)
650 000
43 831 (31 730 to 55 932)
2472
25
1.0 (0.62 to 1.4)
2 259 911
22 855 (13 941 to 31 769)
2088 1081
59 13
2.8 (2.1 to 3.5) 1.2 (0.55 to 1.8)
1 920 541 989 370
53 775 (48 206 to 64 722) 11 872 (5442 to 18 303)
APP, acute pesticide poisoning.
cases had a consistent history of previous acute pesticide exposure and had at least three symptoms or one sign related to the reported pesticide exposure. Information on all self-reported intoxication cases were retained following review. Complete information on case description, including pesticide exposure, severity, health care location and private cost for moderate and severe cases is available in our previous publication.28 The lack of a universally accepted definition of poisoning has been reported as a major difficulty when interpreting the findings of case reports. A recent definition proposed by Thundiyil et al,36 the product of work conducted at the Intergovernmental Forum on Chemical Safety (IFCS), defines an acute pesticide poisoning as ‘‘any illness or health effect resulting from suspected or confirmed exposure to a pesticide within 48 hrs. An acute pesticide poisoning case can be classified as probable, possible or unlikely/unknown’’. According to this proposal, the case definition used in this study refers to ‘‘probable cases’’ as at least one of each exposure, health effect and causality criteria is met: there is a plausible description of exposure reported by patient, there are one sign and/or three or more symptoms compatible with pesticide exposure and there is a temporal cause–effect relationship between exposure and health effect consistent with the known toxicology of the pesticide. This study also proposes that the WHO poisoning severity classification should be complemented with other dimensions of severity, such as medical treatment level and number of work days lost. In fact, we found that these two dimensions showed almost complete overlap with the clinical severity categories. The two dimensions seem to be useful additions to the severity score in terms of evaluating socio-economic cost, including the substantial private economic cost experienced by those poisoned and their families. Our estimated figures excluded fatal cases. Annually, about 200 deaths due to pesticides are reported in Nicaragua. In 2003, the National Institute of Statistics and Census estimated that 50% of all causes of death were under-reported, so we can assume that 400 or more deaths occurred in 2000 due to pesticide poisoning.
Comparison with previous investigations Previous studies of the incidence of acute pesticide poisonings provided information only on exposure and effects in the Occup Environ Med 2009;66:205–210. doi:10.1136/oem.2008.040840
agricultural sector or estimated national figures from official health registries of cases that received medical care. More accurate estimates from such sources were not possible due to under-reporting. We believe that this is the first study which estimates a year-long cumulative incidence of pesticide poisoning in a national population, and which considers both medically treated and untreated acute pesticide poisoning cases. Our source of information was a national survey and most of the self-reported cases did not receive medical attention and were not registered. Compared to data previously reported in the literature,37 38 our study shows a high frequency of intoxications related to pesticide exposure. Also, compared to reports from the official register of the Pesticide Surveillance Program, our findings suggest a very much higher 1-year cumulative incidence. Based on that register, the PAHO found that Nicaragua had one of the highest incidence rates of acute pesticide poisoning in Central America, with over 35 cases per 100 00039 in 2000. However, the 1-year cumulative year incidence rate/100 individuals calculated from our sample was 65 times higher than the official rate. The estimation of intending suicides and domestic accidents were three and 19 times higher than the reported figures, while the occupational figures were extremely high at 115 times the level of official figures.
CONCLUSION This study provides strong evidence that pesticide use in Nicaragua results in a very high cumulative incidence rate of acute pesticide poisonings in Nicaragua. Unlike previous reports on acute pesticide poisoning incidence, this study dealt with the general adult population. It demonstrated that a very substantial proportion of acute pesticide poisonings occurred in an urban population not involved in agricultural or cattle-breeding occupations. Therefore, pesticide poisoning in Nicaragua, rather than primarily being seen as an occupational health concern, should be considered an important general public health problem. Even though our data are from 2000, there are no indications that the situation since has changed. Therefore, it is important that decision makers are fully informed about the magnitude of the pesticide poisoning public health problem in Nicaragua. They must be aware that nearly 66 000 cases of acute pesticide poisonings occur annually and that they should take action to control this problem, including introducing 209
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Original article 10.
Main messages c
c
The study demonstrates that exposure to highly toxic pesticides is widespread in Nicaragua, especially among farmers, agricultural and cattle workers, despite international recommendations. We estimated the 1-year cumulative incidence of acute pesticide poisonings to be 2.3% in the general population above 15 years of age, corresponding to around 66 000 cases, 90% of which are related to occupational exposure.
11. 12. 13. 14. 15. 16. 17.
18.
Policy implications 19. c
c
c
Acute pesticide poisonings should be considered not only as an occupational health concern but an important general public health problem. Decision makers should be informed and take action to control this problem by introducing regulatory measures and promoting alternatives for pest control. Further studies to estimate the economic costs of poisonings for families and health sector institutions should be carried out.
20.
21. 22.
23. 24.
regulatory measures and promoting alternatives for pest control in agriculture, public health and the home. Further studies to estimate the costs of health care for acute poisonings for families and health sector institutions should be developed. Acknowledgements: The authors want to thank all the Nicaraguan participants, especially the 60 field technicians from the Pesticide Program of the Ministry of Health. Funding: This research was supported by the PLAGSALUD Project (Environmental and Occupational Aspects of Pesticide Exposure in Central America, Pan American Health Organization/World Health Organization and the Danish Agency for International Development) and the Research Department of the Swedish International Cooperation Agency. Competing interests: None. Ethics approval: The Nicaraguan National Autonomous University Bioethical Committee in Leon, Nicaragua, reviewed and approved the research protocol.
25.
26. 27. 28. 29.
30.
31.
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