An Economic Evaluation of Environmental Risk of ... - AgEcon Search

Ind. Jn. of Agri.Econ. Vol.62, No.3, July-Sept. 2007

An Economic Evaluation of Environmental Risk of Pesticide Use: A Case Study of Paddy, Vegetables and Cotton in Irrigated Eco-system Alka Singh, Ranjit Kumar and D.K. Das* I INTRODUCTION

Despite the fact that the consequences of injudicious use of pesticides in Asia and other parts of the world are well documented, crop protection continues to be dominated by chemicals. Though negative externalities due to pesticide use cannot be eliminated altogether, their intensity can be minimised through development, dissemination and promotion of environment friendly crop protection technologies. This has further assumed importance, as agriculture has become a subject of international multilateral trade under the WTO/SPS agreements. Many developed countries, of late, apply stringent phyto-sanitary standards and environmentally and socially unacceptable cultivation practices as barriers to international trade. One of the solutions to these problems lies in integrated pest management (IPM) with emphasis on use of non-chemical methods particularly bio-pesticides and bio-agents coupled with improved crop management practices. The present study, therefore, intends to examine pesticide use pattern and adoption of integrated pest management practices in pesticide intensive crops, viz., paddy, vegetables and cotton. Also, the study is directed towards the estimation of environmental risks posed to different components of environment owing to pesticide use in IPM and non-IPM regime of crop protection and farmers’ willingness to pay for safer formulations of pesticides. II DATA AND METHODOLOGY

For the purpose, the study collected farm level data from Karnal and Kaithal districts of Haryana for paddy, Ghaziabad district of Western Uttar Pradesh for vegetables and Bhatinda and Ferozpur districts of Punjab for cotton. These crops were selected purposively as they consume high amount of pesticides. The study area *Principal Scientist, Division of Agricultural Economics, Indian Agricultural Research Institute, New Delhi – 110 012; Senior Scientist (Agril. Economics), Indian Institute of Soil Science, Bhopal and Senior Scientist, National Centre for Integrated Pest Management (NCIPM), New Delhi, respectively. The present paper has been heavily drawn from recently completed ICAR AP Cess funded project on “Pesticide Use and Sustainability of Agriculture: Emerging Issues and Policy Options”.

AN ECONOMIC EVALUATION OF ENVIRONMENTAL RISK OF PESTICIDE USE

493

represented one of the most progressive regions in terms of productivity and input usage and is also characterised by highly commercialised agriculture. For selection of the sample farmers, two top ranking blocks in terms of area under paddy, vegetables and cotton in the respective regions were chosen, and from each selected block, two villages were selected, one where Farmers’ Field School (FFS) on IPM had already been conducted at least two years before the survey and farmers are practising IPM. The other, where no such programme was ever organised and farmers’ were mainly applying chemical pesticides as a means of plant protection. The study is based on primary data, collected for the year 2004-05 from a sample of 120 IPM trained farmers (received formal training regarding IPM in FFS) and 120 NIPM trained farmers (not attended IPM training in FFS) growing paddy, vegetables (tomato and cabbage) and cotton. Environmental Impact of Pesticide Use: The Concept and Model Pesticide risk to the environment is often related to the amount of active ingredient applied or expenditure incurred on pesticides. However, both these measures are not the best indicators of risk because pesticides differ with respect to their toxicity, mobility and persistence and thus pose different levels of risk to different components of the environment. The analysis of the environmental benefits of reduced pesticide use must examine the toxicity, mobility and persistence characteristics of the pesticides being used. If farmers reduce the total quantity of pesticidal active ingredient applied but simultaneously substitute highly toxic, mobile and persistent chemicals for relatively lower quantities, it is difficult to argue that environment has gained (Mullen et al.,1997). Most of the studies have focused on valuing the human health effects of pesticide (Rola and Pingali, 1993) and little attention have been given to other environmental categories. A few studies have suggested the possible approaches for measuring the aggregate environmental costs of pesticides and benefits of IPM (Kovach et al., 1992, Higley and Wintersteen, 1992, Owens et al., 1997, Mullen et al., 1997, Cuyno et al., 2001). The present study identifies five environmental categories, which include human health (acute and chronic effects), animals, birds, aquatic species, and beneficial insects. Active ingredient of each pesticide was assigned three levels of risk, i.e., high, moderate and low for each of the five environmental categories. These risk levels were rated on a scale from one to five with one having a minimal impact on environment or low toxicity and five were considered to be highly toxic or having a major negative effect on the environment.1 Both toxicity and exposure potential criteria were considered in arriving at the assigned risk for each pesticide used in paddy, vegetable and cotton production in the study area. A brief summary of these criteria was presented in Appendix 1.

494

INDIAN JOURNAL OF AGRICULTURAL ECONOMICS

After the data on individuals risk level associated with each environment category were collected, pesticides were grouped by classes (insecticide, fungicide and herbicide) and score assigned to each pesticide active ingredient were combined with usage data to arrive at an overall eco-rating for each pesticide. An overall ecorating score was then calculated separately for IPM and NIPM categories of farmers. The difference between the two represents the amount of risk avoided due to adoption of IPM practices. The formula for eco-rating can be expressed as ESij = (ISj) x (AIi) x (Ratei) Where, ESij is the eco-rating score for active ingredient i and environmental category j, ISj is the pesticide risk score for environmental category j, AIi is the per cent active ingredient in the formulation, and Ratei is the application rate per hectare of i-th active ingredient. The present analysis covers only a single year and pesticide use may vary considerably depending on weather conditions, and this holds true for both IPM as well as non-IPM adopters. Estimating Willingness to Pay for Environmentally Safer Pesticides To examine the farmers’ preference for use of safer pesticides, the values of willingness to pay (WTP) were obtained through contingent valuation (CV) method based on survey of IPM adopters. The respondents were asked to provide WTP values for different formulations of their favourite pesticides. The farmers were offered five pesticide formulations each avoiding risk to specific environmental category (human health, animals, birds, aquatic species and beneficial insects) and asked to rank those five categories whose presence they would be willing to pay more. They were then asked how much if anything they were willing to pay per kg of active ingredient for their most preferred category and their least preferred category. The other categories were valued between the upper and lower bounds of these values. The respondents were given the chance of rearranging their ranks until they were completely satisfied that the rankings and WTP values were representative of their preferences. III RESULTS AND DISCUSSION

Intensity and Composition of Pesticide Use The average quantity (kg. active ingredient), number of applications and expenditure incurred on each category of pesticides (insecticides, fungicides and herbicides) per hectare was calculated for NIPM and IPM farms separately for paddy, vegetables and cotton in the sample area. The results show that on per hectare basis, pesticide use in paddy (non-basmati variety) on sample farms was estimated to be


495

2.47 and 1.85 kg active ingredient (a.i.) respectively on NIPM and IPM adopted farms respectively (Table 1). On an average, paddy crop was treated four times with pesticide, one application each of herbicide and fungicide and two applications of insecticide. Fungicides were used in meager quantities (mainly for seed treatment) whereas, weedicide application was observed to be almost same on both the categories of farmers. Expenditure on pesticides was found higher on NIPM farmers accounting for 15 per cent and 12 per cent of the total cost of paddy cultivation on NIPM and IPM farms, respectively. TABLE 1. PESTICIDE USAGE IN CROP PRODUCTION BY SAMPLE FARMERS

Particulars (1) Paddy Herbicide Insecticide Fungicide Total pesticide No. of application Expenditure (Rs./ha) Tomato Insecticide Fungicide Total pesticide No. of application Expenditure(Rs./ha) Cabbage Insecticide Fungicide Total pesticide No. of application Expenditure (Rs./ha) Cotton Insecticide Fungicide Total pesticide No. of application Expenditure (Rs./ha)

NIPM (2)

Quantity (kg active ingredient/ ha) IPM (3)

1.04 1.33 0.11 2.47 4 1926

0.97 0.85 0.03 1.85 4 1539

2.06 1.65 3.71 9 3208

1.04 0.98 2.02 5 1677

1.39 1.25 2.63 8 2594

0.90 0.71 1.61 5 1442

2.71 --2.71 11 5775

1.98 0.03 2.01 9 3941

In the case of vegetables, the average pesticide use in tomato was found much higher than that of cabbage on both types of farms. In tomato, per hectare consumption of all kinds of pesticides was found to be 3.71 and 2.02 kg active ingredient (a. i.) on NIPM and IPM farms respectively. Similarly on cabbage, pesticide consumption on NIPM and IPM farms was reported to be 2.63 and 1.61 kg a. i. per hectare on sample farms. On an average, tomato and cabbage crops were treated five times with pesticides on IPM farms, whereas, the frequency increased to 9 and 8 times respectively on non-IPM farms. The major pesticides used were

496


insecticides and fungicides. Fungicides constitute less than 50 per cent of total pesticides used in both the crops. In cotton (Hybrids), per hectare consumption was found to be 2.71 and 2.01 kg active ingredient on NIPM and IPM farms respectively. Out of that use of fungicides was found to be extremely low and none of the farmers used herbicides. The expenditure incurred on pesticides was Rs. 5,775 and Rs. 3,941 on NIPM and IPM adopted farms, which account for 26 and 18 per cent of total cost of cultivation respectively. Types of Pesticides Used Pesticide exposure was measured by two criteria, viz., the type of chemical used as well as the quantity along with the number of times they were applied in the crop season. The World Health Organisation (WHO) classified pesticides into five categories (class Ia, Ib, II, III and U) based on their relative acute hazard level, with class Ia as the most hazardous and U as the least one. Though this classification is primarily based on acute hazard level, medical experts suggest that category I and II pesticides are more likely to be associated with chronic hazards (Antle and Pingali, 1994). Hence, pesticides related to these two categories may be seen as posing high and moderate risk, while the pesticides related to rest of the categories may be termed as posing relatively low risks. Paddy farmers in the study area used a number of insecticides, out of which Endosulfan, Cartap hydrochloride, Lambdacyhalothrin and Monocrotophos were prominent among others. All of the insecticides used by sample farmers belonged to either extremely and highly hazardous category (class Ia and Ib) or moderately hazardous (class II) groups as classified by WHO. The principal herbicide used on sample farms was Butachlor, which was classified under Category U according to WHO Classification. Carbandazim, Copper oxychloride, Tricyclazole and Propiconazole were the major fungicides used by sample farmers. Fungicides were used in meager quantity and mostly belong to Category II and U (relatively low risk). Thus, on sample farms, all of the insecticides used were of high and moderate risk category whereas, most of the herbicides used belong to low risk category. Overall, slightly more than 50 per cent of all pesticides used by sample paddy farmers belonged to high and moderate risk category. In the case of vegetables, among pesticides, only insecticides and fungicides were used that too almost in equal proportions. The major insecticide used are cypermethrin, chlorpyriphos, monocrotophos and Endosulfan whereas, mancozeb and copper oxichloride are the major fungicides used in tomato and cabbage cultivation in the study area. Out of the total insecticides and fungicides used in vegetable production, slightly more than 50 per cent belong to high and moderate risk category. Cotton farmers in Punjab use mostly Ethion, Acephate, Trizophos and Monocrotophos in cotton cultivation. Like paddy and vegetables, the share of high and moderate risk pesticides was also observed to be high in the case of cotton. Hence, it can be concluded that not only the


497

intensity of pesticide use but also the high- risk pesticides are being used in crop production in the study area. Adoption of IPM Practices by Sample Farmers The results indicate that among IPM trained farmers, various cultural practices had widespread adoption as against much less adoption of biological practices in all the crops (Table 2). In cultural practices, more than two-third paddy farmers were practicing deep summer ploughing, trimming of bunds, destruction of crop residue, etc. In case of vegetables and cotton, 80 per cent of farmers had practiced deep ploughing, timely planting and destruction of crop residues in the study area. TABLE 2. ADOPTION OF INTEGRATED PEST MANAGEMENT PRACTICES IN SELECTED CROPS Particulars (1) Cultural Practices Deep summer ploughing, trimming of bunds, destruction of crop residues and timely planting Use of resistant/tolerant varieties Avoiding excess nitrogen application Mechanical Practices Use of sex pheromone traps Use of light traps Hand picking of insects Biological Control Release of Trichogramma Use of neem products/neem based pesticides Release of Trichoderma Use of Biveria basiana Use of Bacillus thuringiensis (Bt) Chemical Control Use of pesticides based on ETL

Paddy (2)

(per cent of farmers) Vegetables Cotton (3) (4)

70

80

80

56 54

60 65

58 64

4 21 0

75 0 30

29 0 20

10 24 0 0 0

35 85 80 5 38

0 25 15 15 0

28

60

15

The other practices like use of resistant varieties and balanced fertilisation were also followed by majority of farmers. Among the mechanical practices, pheromone trap was used in paddy by only four per cent of farmers mainly because of farmers’ poor knowledge about its use and non-availability of pest specific lures whereas, it was used by sizeable number of vegetable growers. Only 21 per cent farmers used light traps, however, they also complained about difficulty in using light traps in paddy due to short life as well as non-availability of bulbs. In case of cotton and paddy, use of biological methods for pest control was observed to be very low against moderately high use of those methods by vegetable growers of western Uttar Pradesh Trichogramma was the major bio-agent used in paddy IPM, but its adoption by sample farmers was found to be abysmally low (10 per cent) as against one-third of vegetable farmers. A major problem reported for its low adoption was its slow action against target pest, lack of availability, short shelf life and survival of these bioagents on farmers’ field. Similarly, use of neem pesticide was also found to be low in


498

case of paddy and cotton (25 per cent) due to its erratic supply and high prices. However, in case of vegetable farmers, they were preparing home-based neem formulations and its adoption was found to be significantly high (85 per cent) in the study area. Only 28 per cent of farmers reported using pesticides on the basis of economic threshold levels of pest infestation in paddy growing areas as against 40 per cent of that in case of vegetables and 10 per cent in cotton. Environmental Risk Associated with IPM and Non-IPM Crop Protection Regime The risk scores for most commonly used pesticides in the cultivation of selected crops in the study region for each environment category, i.e., human beings, animals, birds, aquatic and beneficial insects were ascertained as discussed above. Higher values indicate high risk associated with respective pesticide. The scores assigned to each pesticide active ingredient were combined with usage data to arrive at an overall ecological rating for each pesticide. These estimates are presented in Appendix II by each category of pesticide in all the three selected crops. These results show higher aggregate eco- ratings for each environment category on NIPM farms as compared to IPM farms demonstrating higher environmental risk. The estimates presented in Figure 1 show net reduction in eco-ratings due to shift from conventional methods to IPM. It is clearly evident that eco-ratings have reduced to 20 to 30 per cent as a result of adoption of IPM practices by IPM farmers in each paddy growing season. Similar results were also reported in Western Uttar Pradesh where IPM is being practiced in vegetable cultivation. The estimates revealed that eco-ratings have declined to 39 to 46 per cent as a result of adoption of IPM practices in tomato and cabbage cultivation in each season. Paddy

Vegetables

Cotton

Percent Risk avoided

50 46

40

41

39 30 30

40

37 32

40 31

26

20

20

20

10 0 Human beings

Birds

Aquatic species

Beneficial insects

Figure 1. Estimated Reduction in Environmental Risk from Pesticide Use Due to IPM in Paddy, Vegetables and Cotton


499

In the case of cotton, due to IPM practices eco-ratings had reduced by 31 to 40 per cent in different environment categories. These reductions represent the per cent pesticide risk avoided due to reduced pesticide application as well as judicious selection of environment friendly pesticides on IPM farms in crop cultivation in the study area. Farmers’ Willingness to Pay for Safer Pesticides The results showed that in the case of paddy cultivation, 41 per cent of the sample farmers ranked first the safer pesticides for human beings as the most preferred category. They were willing to pay up to 30 per cent price premium for those formulations that are certified to have no or least harmful effects on human health. The average willingness (WTP) to pay for those pesticides was estimated as 10 per cent over the present value. However, more than 50 per cent respondents rated pesticide safer for beneficial insects as the most preferred one. For that characteristic, they were found to be ready to pay a maximum of 33 per cent higher prices (Table 3). TABLE 3. FARMERS’ WILLINGNESS TO PAY (WTP) FOR SAFER FORMULATIONS OF PESTICIDES

Environmental category (1) Paddy Human Beneficial insects Vegetables Human Beneficial insects Cotton Human Beneficial insects

Farmers opting for first choice (2)

Average WTP (3)

(per cent) Max WTP (4)

41.38 55.17

10.00 13.96

30.00 33.00

30.00 67.50

16.38 21.75

40.00 38.00

15.00 85.00

18.75 25.50

30.00 50.00

Similarly in the case of vegetable cultivation in western Uttar Pradesh, more than two-third of the sample farmers expressed their first choice towards safer pesticides formulations for beneficial insects. For that, farmers were ready to pay on an average 30 per cent higher prices than what they are paying today. Those who had ranked human health as the first category were found to be willing to pay a maximum of 40 per cent. Aquatic, animals and birds are the least preferred environment category as regards the willingness to pay is concerned in all the crop regimes. These results confirm that a market exists for safer or environment friendly pesticides in the study area.

500


IV CONCLUSIONS

The study revealed that not only the intensity of pesticide use was high but also the high risk pesticides are being used in crop production both by IPM adopters as well as non-adopters in the study area. This has profound implications for agricultural sustainability. The results suggest that among IPM trained farmers, various cultural practices, which are practiced as a matter of tradition, had widespread adoption as against low adoption of biological practices in all the crops. The major constraints reported for low adoption of biological methods was its slow action against target pest, lack of availability, short shelf life and survival of bio-agents in the field, high prices and irregular supply of neem pesticides etc. In spite of that, the study clearly shows that even partial adoption of different IPM practices by the sample farmers has the potential of avoiding pesticide risk hazards to different environment categories by 20-30 per cent in paddy cultivation and 39 to 46 per cent in vegetable cultivation and 31 per cent to 40 per cent in cotton. The study estimated the farmers’ willingness to pay for pesticides hazard reduction for five environmental categories. These results clearly show that a market exists for environment friendly pesticides in the study area and farmers are willing to pay a premium price for reduction of pesticide hazards. Hence, pesticide risk to environment can be successfully reduced by developing farmers’ own capacity by imparting information and awareness, development of simple and safer methods of pest control and assuring their adequate supply would go a long way in reducing pesticide risks to the environment. NOTE 1. Extensive data are available on the environmental effects of specific pesticides, and the data used in this study were gathered from a variety of sources. The Extension Toxicology Network (EXTOXNET), a collaborative education project of the environmental toxicology and pesticide education departments of Cornell University, Michigan University, Oregon University and the University of California, was the primary source used in developing the database. EXTOXNET conveys pesticide related information on the health and environmental effects of approximately 100 pesticides. Other sources of information used were CHEM-NEWS, Pesticide Manual and previous studies. REFERENCES Antle, J. M. and P. L. Pingali (1994), “Pesticides, Productivity, and Farmer Health: A Filipino Case Study”, American Journal of Agricultural Economics, Vol.76, pp.418-430. Blessing, M. Manumbe and Scott M. Swinton (2000), “Why Do Smallholder Cotton Growers in Zimbabwe Adopt IPM? The Role of Pesticide-Related Health Risks and Technology Awareness”, Presented at the Annual Meeting of the American Agricultural Economics Association, Tampa, FL, July 30-August 2. Cuyno, Leach C.M.; George W. Norton and Agenes Rola (2001), “Economic Analysis of Environmental Benefits of Integrated Pest Management: A Philippine Case Study”, Agricultural Economics, Vol.25, pp.227-233. EXTOXNET, [Multi-university computer network providing toxicity –related electronic data; data base available on Oregon state server.] online available at http://extoxnet.orst.edu/pips/


501

Higley, L.G. And W. K. Wintersteen (1992), “A Novel Approach to Environmental Risk Assessment of Pesticides as a Basis for Incorporating Environmental Costs into Economic Injury Level.” American Entomologist, Vol.38, pp.34-39. Kovach, J., C. Petzoldt, J. Degni, and J. Tette (1992), “A Method to Measure the Environmental Impact of Pesticides” New York’s Food and Life Science Bulletin, No. 139, New York State Agr. Exp. Sta., Cornell University, Ithaca. Mullen, D. Jeffery; George W. Norton, and Dixie W. Reaves (1997), “Economic Analysis of Environmental Benefits of Integrated Pest Management”, Journal of Agricultural and Applied Economics, Vol.29, No.2, pp.243-253. Owens, N.N.; S.M. Swinton, and E.O. Van Ravenswaay (1997), Farmer Demand for Safer Corn Herbicides: Survey Methods and Descriptive Results, Michigan Agricultural Experiment Station, Michigan State University. Research Report 547, East Lansing, MI. Rola, A.C. and P.L. Pingali (1993), Pesticides, Rice Productivity, and Farmers’ Health: An Economic Assessment, International Rice Research Institute, The Philippines and World Resources Institute, Washington, D.C., U.S.A. APPENDIX 1 PESTICIDE IMPACT SCORING SYSTEM Environmental categories (1) I Human Health 1.Toxicity Acute Toxicity

Chronic toxicity 2. Exposure Leaching potential Run-off potential 3. Food residues

II. Aquatic Species 1. Toxicity

2. Exposure III. Beneficial Insects 1. Toxicity 2. Exposure IV. Mammalian Farm Animals V. Birds 1.Toxicity 2. Exposure

Indicators (2)

High Risk = 5 (3)

Score Moderate risk = 3 (4)

Low risk = 1 (5)

Pesticide Class (WHO Criteria) Signal Word (EPA Criteria) Weight of Evidence of chronic effects

Ia; Ib Danger / Poison

II Warning

III Caution

Conclusive Evidence

Probable Evidence

Inconclusive Evidence

Leaching potential score Soil half life Systemicity

High High -

Plant surface residues half Life

> 4 weeks

Moderate Moderate Systemic, postemergent 2-4 weeks

Low Low Non-systemic, Pre-emergent 1-2 weeks

95 hr LC50 (fish) mg/L Fish / other aquatic species toxicity Run-off Potential Score

10 ppm

High

Moderate

Low

Insect Toxicity Ratings Plant Surface Residue Half life For animals and human beings, same level of risk has been assumed.

Extreme / High > 4 weeks

Moderate 2-4 weeks

Low 1-2 weeks

Birds Toxicity Ratings 8 days LD50 Plant Surface Half- life

High/Extreme 4 weeks

Moderate 100-500 ppm 2-4 weeks

Low > 500 ppm 1-2 weeks

502


APPENDIX II ENVIRONMENTAL RISK ASSOCIATED WITH PESTICIDE USE IN PADDY, VEGETABLES AND COTTON BY NIPM AND IPM CATEGORIES OF FARMERS Eco-ratings (Paddy)

Eco-ratings Eco-ratings (cotton) (Vegetables) NIPM IPM NIPM IPM NIPM IPM Types of farmers farmers farmers farmers farmers farmers Category pesticide (3) (4) (5) (6) (7) (8) (1) (2) Herbicide 42.89 40.64 Human beings Insecticide 214.90 138.32 238.38 137.10 297.78 439.16 Fungicide 6.86 6.06 96.36 66.57 2.22 1.85 Herbicide 42.89 40.64 Animals Insecticide 214.90 138.32 238.38 137.10 297.78 439.16 Fungicide 6.86 6.06 96.36 66.57 2.22 1.85 Herbicide 39.35 35.62 Birds Insecticide 143.11 100.46 196.70 117.52 298.13 468.72 Fungicide 9.44 5.74 96.67 56.62 1.24 3.09 Herbicide 187.62 171.01 Aquatic species Insecticide 208.54 144.00 219.69 133.58 389.02 563.01 Fungicide 9.73 6.78 191.21 111.52 2.47 3.09 Herbicide 112.47 105.78 Beneficial insects Insecticide 131.75 90.62 230.83 121.67 225.48 373.53 Fungicide 2.29 2.02 57.40 33.59 0.74 0.62 Note: No herbicide use was reported by sample farmers in vegetables and cotton cultivation.