Pesticide Use and Serum Acetylcholinesterase Levels among Flower Farm Workers in Ethiopia—A Cross-Sectional Study
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area and Design
2.2. Sample Size Determination
2.3. Selection of Farms and Sampling Procedure
2.4. Interviews, Blood Sampling and Laboratory Analysis of Serum Cholinesterase Level
2.5. Collection of Data on the Types and Usage of Pesticides
2.5.1. Walkthrough Survey
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- The work process of pesticide mixing and spraying, greenhouse work and packinghouse work.
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- Pesticide mixing and storage. Chemical stores were visited and lists of pesticides in use with their active ingredients were obtained from storekeepers with permission from the farm managers.
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- The use of personal protective equipment by workers (boots, overalls, gloves, respirators, goggles and aprons).
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- Ventilation: Mechanical or natural (presence of windows).
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- Re-entry times in sprayed greenhouses. Production managers who assisted us in the walkthrough survey were asked how much time is required before workers can re-enter the greenhouse.
2.5.2. Evaluation of Lists of Pesticides
2.6. Data Management and Statistical Analysis
2.7. Ethical Consideration
3. Results
3.1. Characteristics of the Participants
3.2. Serum Cholinesterase Level
3.3. Pesticide Use in the Flower Farms
3.3.1. Workplace Assessment
3.3.2. Types of Pesticides Used on the Flower Farms
4. Discussion
5. Conclusions and Recommendations
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Workers | Total | Farm | |||||
---|---|---|---|---|---|---|---|
1 | 2 | 3 | 4 | 5 | 6 | ||
Total number of female greenhouse workers | 1282 | 225 | 112 | 256 | 242 | 237 | 210 |
Total number of invited female greenhouse workers | 160 | 28 | 14 | 32 | 30 | 30 | 26 |
Number of participating female greenhouse workers | 156 | 27 | 13 | 32 | 30 | 30 | 24 |
Total number of female packinghouse workers | 324 | 54 | 50 | 60 | 63 | 57 | 40 |
Total number of invited female packinghouse workers | 160 | 28 | 25 | 29 | 30 | 28 | 20 |
Number of participating female packinghouse workers | 155 | 28 | 23 | 28 | 30 | 26 | 20 |
Variables | All Workers | Working Section Females/Males | Sex | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Green-House (n = 156) | Packinghouse (n = 155) | p-Value | Sprayers (n = 148) | Non-Sprayers (n = 129) | p-Value | Male (n= 277) | Female (n = 311) | p-Value | |||
Mean age in years (SD) | 25 (7) | 25 (8) | 24 (7) | 0.08 1 | 27 (6) | 26 (7) | 0.66 1 | 26 (7) | 25 (7) | <0.01 1 | |
Mean working months on current farm (SD) | 32 (33) | 30 (31) | 31 (27) | 0.66 1 | 32 (31) | 38 (43) | 0.17 1 | 34 (37) | 31 (29) | 0.16 1 | |
Mean working hours (SD) per day | 7.4 (1.3) | 7.9 (0.5) | 8 (0.3) | 0.03 1 | 5.7 (1.6) | 7.9 (0.5) | <0.01 1 | 6.7 (1.6) | 7.9 (0.4) | <0.01 1 | |
Mean body mass index (SD) | 20.3 (2.4) | 20.6 (2.6) | 20.8 (2.5) | 0.74 1 | 19.9 (2.0) | 19.8 (2.1) | 0.47 1 | 19.8 (2.0) | 20.7 (2.6) | <0.01 1 | |
Educational level | Unable to read and write n (%) | 88 (20.0) | 39 (25.0) | 16 (10.3) | <0.01 2 | 19 (12.8 | 14 | 0.61 2 | 33 (11.9) | 55 (17.7) | 0.05 2 |
Able to read and write n (%) | 500 (80.0) | 117 (75.0) | 139 (89.7) | 129 | 115 | 244 (88.1) | 256 (82.3) | ||||
Transferred ever from other work section | Yes n (%) | 62 (10.5) | 2 (1.3) | 22 (14.2) | <0.01 2 | 17 (11.5) | 21 (16.3) | 0.251 2 | 38 (13.7) | 24 (7.7) | 0.02 2 |
No n (%) | 526 (89.5) | 154 (98.7) | 133 (85.8) | 131 (88.5) | 108 (83.7) | 239 (86.3) | 287 (92.3) | ||||
Worked on other flower farm | Yes n (%) | 133 (22.6) | 32 (20.5) | 32 (20.7) | 0.97 2 | 36 (24.3) | 33 (25.6) | 0.80 2 | 69 (24.9) | 64 (20.6) | 0.21 2 |
No n (%) | 455 (77.4) | 124 (79.5) | 123 (79.4) | 112 (75.7) | 96 (74.4) | 208 (75.1) | 247 (79.4) | ||||
Ever drinking alcohol | Yes n (%) | 291 (49.5) | 56 (35.9) | 51 (32.9) | 0.56 2 | 86 (58.9) | 98 (75.9) | <0.01 2 | 184 (66.4) | 107 (34.3) | <0.01 2 |
No n (%) | 297 (50.5) | 100 (64.1) | 104 (67.1) | 62 (41.9) | 31 (24.0) | 93 (33.6) | 204 (65.6) | ||||
Own farm | Yes n (%) | 105 (17.9) | 11 (7.1) | 7 (4.6) | 0.34 2 | 58 (39.2) | 29 (22.5) | <0.012 | 87 (31.4) | 18 (5.8) | <0.01 2 |
No n (%) | 483 (82.1) | 145 (93.0) | 148 (95.5) | 90 (60.8) | 100 (77.5) | 190 (68.6) | 293 (94.2) |
Characteristics | SCHE in MU AM(SD) | p-Value (t-Test) | Range | No. of SCHE above 140 MU (%) (95% CI) | Prevalence ratio 95% CI | |
---|---|---|---|---|---|---|
Female workers (n = 311) | ||||||
Work section | Greenhouse workers (n =156) | 116.2 (29.3) | 0.42 | 51–189 | 27 (17.4) (12.1–24.1) | 0.9 (0.89–1.09) |
Packinghouse workers (n = 155) | 118.7 (25.3) | 50–190 | 25 (16.1 (11.1–22.8)) | 1 | ||
Service year | <5 years (n = 244) | 118.1 (27.8) | 0.42 | 50–190 | 42 (17.2) (13.0–22.5) | 1.04 (0.91–1.18) |
≥5years (n = 67) | 115.1 (27.5) | 69–189 | 10 (14.9) (8.2–25.7) | 1 | ||
Transferred from Other work section | Yes (n = 24) | 116.1 (26.0) | 0.65 | 81–174 | 2 (8.3) (2.0–28.6) | 1.11(0.94−1.30) |
No (n = 287) | 117.8 (27.7) | 50–190 | 50 (17.4) (13.4–22.3) | |||
Male workers (n = 277) | ||||||
Work section (n = 277) | Sprayers (n = 148) | 116.1 (25.9) | 0.85 | 77–190 | 23 (15.5) (10.5–22.4) | 1.03 (0.29–1.14) |
Non-sprayers (n = 129) | 115.5 (24.2) | 64–164 | 23 (17.8) (12.1–25.5) | 1 | ||
Working years | <5 years (n = 218) | 115.3 (25.0) | 0.49 | 70–190 | 36 (16.5) (12.1–22.1) | 1.04 (0.89–1.21) |
≥5 years (n = 59) | 117.8 (25.4) | 64–189 | 10 (16.9) (9.3–28.9) | |||
Transferred from other work section | Yes (n = 38) | 117.2 (22.8) | 0.15 | 70–164 | 7 (18.3) (8.9–34.2) | 0.99 (0.84–1.16) |
No (n = 239) | 112.1 (25.6) | 64–190 | 39 (16.3) (12.1–21.6) | |||
Own farm | Yes (n = 87) | 118.6 (25.5) | 0.21 | 76–183 | 13 (14.9) (8.8–24.2) | 1.04 (0.92−1.17) |
No (n = 190) | 114.6 (24.8 | 64–190 | 33 (17.4) (13.6–23.5) | |||
Total workers (n = 588) | ||||||
Work section | Sprayers (n = 148) | 116.1 (25.9) | 0.75 | 77–190 | 23 (15.3) (10.5–22.3) | 1.03 (0.95–1.12) |
Non-sprayers (n = 440) | 116.9 (26.4) | 50–190 | 75 (17.05) (13.8–20.9) | 1 | ||
Working years | <5 years (n = 462) | 116.8 (26.5) | 0.87 | 50–190 | 78 (16.9) (13.7–20.6) | 1 |
≥5 years (n = 126) | 116.4 (25.4) | 64–189 | 20 (15.9) (10.4–23.4) | 1.01 (0.92–1.10) | ||
Transferred from other work section | Yes (n = 62) | 117.9 (22.9) | 0.70 | 70–174 | 9 (14.5 (7.7–25.7)) | 1.03 (0.92–1.15 |
No (n = 526) | 116.626.7) | 50–190 | 89 (16.9 (13.9–20.4)) | 1 |
Classification | All Farms n = 113 No. (%) | Farm 1 n = 25 No. (%) | Farm 2 n = 16 No. (%) | Farm 3 n = 29 No. (%) | Farm 4 n = 36 No. (%) | Farm 5 n = 31 No. (%) | Farm 6 n = 50 No. (%) | |
---|---|---|---|---|---|---|---|---|
WHO classification | Highly hazardous (IB) | 1 (0.9) | 1 (4.0) | 0 | 0 | 0 | 0 | 0 |
Moderately hazardous (II) | 31 (27.4) | 3 (12.0) | 9 (56.3) | 6 (20.7) | 5 (13.9) | 10 (32.3) | 18 (36.0) | |
Slightly hazardous (III) | 17 (15.0) | 3 (12.0) | 3 (18.8) | 7 (24.1) | 7 (19.4) | 4 (12.9) | 4 (8.0) | |
Unlikely to be hazardous | 23 (20.4) | 5 (20.0) | 2 (12.5) | 5 (17.2) | 10 (27.8) | 7 (22.5) | 8 (16.0) | |
Classes could not be traced | 41 (36.3) | 13 (52.0) | 2 (12.5) | 11 (37.9) | 14 (38.9) | 10 (32.3) | 20 (40.0) | |
Chemical Classes of Pesticides | Organophosphates | 10 (8.9) | 2 (8.0) | 2 (12.5) | 5 (17.2) | 1 (2.8) | 3 (9.7) | 6 (12.0) |
Neonicotinoids | 10 (8.9) | 1 (4.0) | 3 (18.8) | 2 (6.9) | 4 (11.1) | 3 (9.7) | 3 (6.0) | |
Pyrethroids | 10 (8.9) | 1 (4.0) | 0 | 1 (3.4) | 3 (8.3) | 1 (3.2) | 5 (10.0) | |
Inorganic | 9 (8.0) | 2 (8.0) | 1 (6.3) | 4 (13.8) | 0 | 1 (3.2) | 4 (8.0) | |
Unclassified | 52 (46.0) | 3 (12.0) | 0 | 3 (3.4) | 10 (27.8) | 9 (29.0) | 4 (8.0) | |
Others | 22 (19.5) | 16 (64.0) | 10 (62.5) | 14 (48.3) | 18 (50.0) | 14 (45.2) | 28 (56.0) |
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Shentema, M.G.; Kumie, A.; Bråtveit, M.; Deressa, W.; Ngowi, A.V.; Moen, B.E. Pesticide Use and Serum Acetylcholinesterase Levels among Flower Farm Workers in Ethiopia—A Cross-Sectional Study. Int. J. Environ. Res. Public Health 2020, 17, 964. https://doi.org/10.3390/ijerph17030964
Shentema MG, Kumie A, Bråtveit M, Deressa W, Ngowi AV, Moen BE. Pesticide Use and Serum Acetylcholinesterase Levels among Flower Farm Workers in Ethiopia—A Cross-Sectional Study. International Journal of Environmental Research and Public Health. 2020; 17(3):964. https://doi.org/10.3390/ijerph17030964
Chicago/Turabian StyleShentema, Meaza Gezu, Abera Kumie, Magne Bråtveit, Wakgari Deressa, Aiwerasia Vera Ngowi, and Bente E. Moen. 2020. "Pesticide Use and Serum Acetylcholinesterase Levels among Flower Farm Workers in Ethiopia—A Cross-Sectional Study" International Journal of Environmental Research and Public Health 17, no. 3: 964. https://doi.org/10.3390/ijerph17030964
APA StyleShentema, M. G., Kumie, A., Bråtveit, M., Deressa, W., Ngowi, A. V., & Moen, B. E. (2020). Pesticide Use and Serum Acetylcholinesterase Levels among Flower Farm Workers in Ethiopia—A Cross-Sectional Study. International Journal of Environmental Research and Public Health, 17(3), 964. https://doi.org/10.3390/ijerph17030964