Skip to main content
PMC home page
Environmental Health Perspectives logoLink to Environmental Health Perspectives
. 2003 Nov;111(14):1765–1772. doi: 10.1289/ehp.6341

Neurobehavioral performance and work experience in Florida farmworkers.

Freya Kamel 1, Andrew S Rowland 1, Lawrence P Park 1, W Kent Anger 1, Donna D Baird 1, Beth C Gladen 1, Tirso Moreno 1, Lillian Stallone 1, Dale P Sandler 1
PMCID: PMC1241721  PMID: 14594629

Abstract

Farmworkers experience many work-related hazards, including exposure to neurotoxicants. We compared neurobehavioral performance of 288 farmworkers in central Florida who had done farm work for at least 1 month with 51 controls who had not. Most of the farmworkers had worked in one or more of three types of agriculture: ornamental ferns, nurseries, or citrus fruit. We collected information on farm work history in a structured interview and evaluated neurobehavioral performance using a battery of eight tests. Analyses were adjusted for established confounders including age, sex, education, and acculturation. Ever having done farm work was associated with poor performance on four tests--digit span [odds ratio (OR) = 1.90; 95% confidence interval (CI), 1.02-3.53], tapping (coefficient = 4.13; 95% CI, 0.00-8.27), Santa Ana test (coefficient = 1.34; 95% CI, 0.29-2.39), and postural sway (coefficient = 4.74; 95% CI, -2.20 to 11.7)--but had little effect on four others: symbol digit latency, vibrotactile threshold, visual contrast sensitivity, and grip strength. Associations with farm work were similar in magnitude to associations with personal characteristics such as age and sex. Longer duration of farm work was associated with worse performance. Associations with fern work were more consistent than associations with nursery or citrus work. Deficits related to the duration of work experience were seen in former as well as current farmworkers, and decreased performance was related to chronic exposure even in the absence of a history of pesticide poisoning. We conclude that long-term experience of farm work is associated with measurable deficits in cognitive and psychomotor function.

Full Text

The Full Text of this article is available as a PDF (136.3 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ames R. G., Steenland K., Jenkins B., Chrislip D., Russo J. Chronic neurologic sequelae to cholinesterase inhibition among agricultural pesticide applicators. Arch Environ Health. 1995 Nov-Dec;50(6):440–444. doi: 10.1080/00039896.1995.9935980. [DOI] [PubMed] [Google Scholar]
  2. Anger W. K., Cassitto M. G., Liang Y. X., Amador R., Hooisma J., Chrislip D. W., Mergler D., Keifer M., Hörtnagl J., Fournier L. Comparison of performance from three continents on the WHO-Recommended Neurobehavioral Core Test Battery. Environ Res. 1993 Jul;62(1):125–147. doi: 10.1006/enrs.1993.1097. [DOI] [PubMed] [Google Scholar]
  3. Anger W. K., Liang Y. X., Nell V., Kang S. K., Cole D., Bazylewicz-Walczak B., Rohlman D. S., Sizemore O. J. Lessons learned--15 years of the WHO-NCTB: a review. Neurotoxicology. 2000 Oct;21(5):837–846. [PubMed] [Google Scholar]
  4. Anger W. K., Sizemore O. J., Grossmann S. J., Glasser J. A., Letz R., Bowler R. Human neurobehavioral research methods: impact of subject variables. Environ Res. 1997;73(1-2):18–41. doi: 10.1006/enrs.1997.3707. [DOI] [PubMed] [Google Scholar]
  5. Anger W. Kent. Neurobehavioural tests and systems to assess neurotoxic exposures in the workplace and community. Occup Environ Med. 2003 Jul;60(7):531-8, 474. doi: 10.1136/oem.60.7.531. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bazylewicz-Walczak B., Majczakowa W., Szymczak M. Behavioral effects of occupational exposure to organophosphorous pesticides in female greenhouse planting workers. Neurotoxicology. 1999 Oct;20(5):819–826. [PubMed] [Google Scholar]
  7. Ciesielski S., Loomis D. P., Mims S. R., Auer A. Pesticide exposures, cholinesterase depression, and symptoms among North Carolina migrant farmworkers. Am J Public Health. 1994 Mar;84(3):446–451. doi: 10.2105/ajph.84.3.446. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Das R., Steege A., Baron S., Beckman J., Harrison R. Pesticide-related illness among migrant farm workers in the United States. Int J Occup Environ Health. 2001 Oct-Dec;7(4):303–312. doi: 10.1179/107735201800339272. [DOI] [PubMed] [Google Scholar]
  9. Dick R. B., Steenland K., Krieg E. F., Hines C. J. Evaluation of acute sensory--motor effects and test sensitivity using termiticide workers exposed to chlorpyrifos. Neurotoxicol Teratol. 2001 Jul-Aug;23(4):381–393. doi: 10.1016/s0892-0362(01)00143-x. [DOI] [PubMed] [Google Scholar]
  10. Engel L. S., Keifer M. C., Checkoway H., Robinson L. R., Vaughan T. L. Neurophysiological function in farm workers exposed to organophosphate pesticides. Arch Environ Health. 1998 Jan-Feb;53(1):7–14. doi: 10.1080/00039899809605684. [DOI] [PubMed] [Google Scholar]
  11. Farahat T. M., Abdelrasoul G. M., Amr M. M., Shebl M. M., Farahat F. M., Anger W. K. Neurobehavioural effects among workers occupationally exposed to organophosphorous pesticides. Occup Environ Med. 2003 Apr;60(4):279–286. doi: 10.1136/oem.60.4.279. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Fiedler N., Kipen H., Kelly-McNeil K., Fenske R. Long-term use of organophosphates and neuropsychological performance. Am J Ind Med. 1997 Nov;32(5):487–496. doi: 10.1002/(sici)1097-0274(199711)32:5<487::aid-ajim8>3.0.co;2-p. [DOI] [PubMed] [Google Scholar]
  13. Gomes J., Lloyd O. L., Revitt D. M. The influence of personal protection, environmental hygiene and exposure to pesticides on the health of immigrant farm workers in a desert country. Int Arch Occup Environ Health. 1999 Jan;72(1):40–45. doi: 10.1007/s004200050332. [DOI] [PubMed] [Google Scholar]
  14. Kamel F., Moreno T., Rowland A. S., Stallone L., Ramírez-Garnica G., Sandler D. P. Recruiting a community sample in collaboration with farmworkers. Environ Health Perspect. 2001 Jun;109 (Suppl 3):457–459. doi: 10.1289/ehp.01109s3457. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Katz J. N., Larson M. G., Fossel A. H., Liang M. H. Validation of a surveillance case definition of carpal tunnel syndrome. Am J Public Health. 1991 Feb;81(2):189–193. doi: 10.2105/ajph.81.2.189. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Keifer M. C., Mahurin R. K. Chronic neurologic effects of pesticide overexposure. Occup Med. 1997 Apr-Jun;12(2):291–304. [PubMed] [Google Scholar]
  17. Kilburn K. H., Thornton J. C., Hanscom B. Population-based prediction equations for neurobehavioral tests. Arch Environ Health. 1998 Jul-Aug;53(4):257–263. doi: 10.1080/00039899809605706. [DOI] [PubMed] [Google Scholar]
  18. Krieg E. F., Jr, Chrislip D. W., Letz R. E., Otto D. A., Crespo C. J., Brightwell W. S., Ehrenberg R. L. Neurobehavioral test performance in the third National Health and Nutrition Examination Survey. Neurotoxicol Teratol. 2001 Nov-Dec;23(6):569–589. doi: 10.1016/s0892-0362(01)00177-5. [DOI] [PubMed] [Google Scholar]
  19. London L., Myers J. E., Nell V., Taylor T., Thompson M. L. An investigation into neurologic and neurobehavioral effects of long-term agrichemical use among deciduous fruit farm workers in the Western Cape, South Africa. Environ Res. 1997;73(1-2):132–145. doi: 10.1006/enrs.1997.3715. [DOI] [PubMed] [Google Scholar]
  20. London L., Nell V., Thompson M. L., Myers J. E. Effects of long-term organophosphate exposures on neurological symptoms, vibration sense and tremor among South African farm workers. Scand J Work Environ Health. 1998 Feb;24(1):18–29. doi: 10.5271/sjweh.274. [DOI] [PubMed] [Google Scholar]
  21. McConnell R., Keifer M., Rosenstock L. Elevated quantitative vibrotactile threshold among workers previously poisoned with methamidophos and other organophosphate pesticides. Am J Ind Med. 1994 Mar;25(3):325–334. doi: 10.1002/ajim.4700250303. [DOI] [PubMed] [Google Scholar]
  22. Moses M., Johnson E. S., Anger W. K., Burse V. W., Horstman S. W., Jackson R. J., Lewis R. G., Maddy K. T., McConnell R., Meggs W. J. Environmental equity and pesticide exposure. Toxicol Ind Health. 1993 Sep-Oct;9(5):913–959. doi: 10.1177/074823379300900512. [DOI] [PubMed] [Google Scholar]
  23. Ohayo-Mitoko G. J., Kromhout H., Simwa J. M., Boleij J. S., Heederik D. Self reported symptoms and inhibition of acetylcholinesterase activity among Kenyan agricultural workers. Occup Environ Med. 2000 Mar;57(3):195–200. doi: 10.1136/oem.57.3.195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Pilkington A., Buchanan D., Jamal G. A., Gillham R., Hansen S., Kidd M., Hurley J. F., Soutar C. A. An epidemiological study of the relations between exposure to organophosphate pesticides and indices of chronic peripheral neuropathy and neuropsychological abnormalities in sheep farmers and dippers. Occup Environ Med. 2001 Nov;58(11):702–710. doi: 10.1136/oem.58.11.702. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Rohlman D. S., Bailey S. R., Anger W. K., McCauley L. Assessment of neurobehavioral function with computerized tests in a population of hispanic adolescents working in agriculture. Environ Res. 2001 Jan;85(1):14–24. doi: 10.1006/enrs.2000.4105. [DOI] [PubMed] [Google Scholar]
  26. Rohlman D. S., Bailey S. R., Brown M., Blanock M., Anger W. K., McCauley L. Establishing stable test performance in tests from the Behavioral Assessment and Research System (BARS). Neurotoxicology. 2000 Oct;21(5):715–723. [PubMed] [Google Scholar]
  27. Rohlman D. S., Gimenes L. S., Ebbert C., Anger W. K., Bailey S. R., McCauley L. Smiling faces and other rewards: using the Behavioral Assessment and Research System (BARS) with unique populations. Neurotoxicology. 2000 Dec;21(6):973–978. [PubMed] [Google Scholar]
  28. Rohlman Diane S., Gimenes Lincoln S., Eckerman David A., Kang Seong-Kyu, Farahat Fayssal M., Anger W. Kent. Development of the Behavioral Assessment and Research System (BARS) to detect and characterize neurotoxicity in humans. Neurotoxicology. 2003 Aug;24(4-5):523–531. doi: 10.1016/s0161-813x(03)00023-8. [DOI] [PubMed] [Google Scholar]
  29. Rosenstock L., Keifer M., Daniell W. E., McConnell R., Claypoole K. Chronic central nervous system effects of acute organophosphate pesticide intoxication. The Pesticide Health Effects Study Group. Lancet. 1991 Jul 27;338(8761):223–227. doi: 10.1016/0140-6736(91)90356-t. [DOI] [PubMed] [Google Scholar]
  30. Ruijten M. W., Sallé H. J., Verberk M. M., Smink M. Effect of chronic mixed pesticide exposure on peripheral and autonomic nerve function. Arch Environ Health. 1994 May-Jun;49(3):188–195. doi: 10.1080/00039896.1994.9940381. [DOI] [PubMed] [Google Scholar]
  31. Sack D., Linz D., Shukla R., Rice C., Bhattacharya A., Suskind R. Health status of pesticide applicators: postural stability assessments. J Occup Med. 1993 Dec;35(12):1196–1202. [PubMed] [Google Scholar]
  32. Savage E. P., Keefe T. J., Mounce L. M., Heaton R. K., Lewis J. A., Burcar P. J. Chronic neurological sequelae of acute organophosphate pesticide poisoning. Arch Environ Health. 1988 Jan-Feb;43(1):38–45. doi: 10.1080/00039896.1988.9934372. [DOI] [PubMed] [Google Scholar]
  33. Steenland K., Dick R. B., Howell R. J., Chrislip D. W., Hines C. J., Reid T. M., Lehman E., Laber P., Krieg E. F., Jr, Knott C. Neurologic function among termiticide applicators exposed to chlorpyrifos. Environ Health Perspect. 2000 Apr;108(4):293–300. doi: 10.1289/ehp.00108293. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Steenland K., Jenkins B., Ames R. G., O'Malley M., Chrislip D., Russo J. Chronic neurological sequelae to organophosphate pesticide poisoning. Am J Public Health. 1994 May;84(5):731–736. doi: 10.2105/ajph.84.5.731. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Stephens R., Spurgeon A., Berry H. Organophosphates: the relationship between chronic and acute exposure effects. Neurotoxicol Teratol. 1996 Jul-Aug;18(4):449–453. doi: 10.1016/0892-0362(96)00028-1. [DOI] [PubMed] [Google Scholar]
  36. Stephens R., Spurgeon A., Calvert I. A., Beach J., Levy L. S., Berry H., Harrington J. M. Neuropsychological effects of long-term exposure to organophosphates in sheep dip. Lancet. 1995 May 6;345(8958):1135–1139. doi: 10.1016/s0140-6736(95)90976-1. [DOI] [PubMed] [Google Scholar]
  37. Stokes L., Stark A., Marshall E., Narang A. Neurotoxicity among pesticide applicators exposed to organophosphates. Occup Environ Med. 1995 Oct;52(10):648–653. doi: 10.1136/oem.52.10.648. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Villarejo D., Baron S. L. The occupational health status of hired farm workers. Occup Med. 1999 Jul-Sep;14(3):613–635. [PubMed] [Google Scholar]
  39. Wesseling Catharina, Keifer Matthew, Ahlbom Anders, McConnell Rob, Moon Jai-Dong, Rosenstock Linda, Hogstedt Christer. Long-term neurobehavioral effects of mild poisonings with organophosphate and n-methyl carbamate pesticides among banana workers. Int J Occup Environ Health. 2002 Jan-Mar;8(1):27–34. doi: 10.1179/oeh.2002.8.1.27. [DOI] [PubMed] [Google Scholar]
  40. van Wendel de Joode B., Wesseling C., Kromhout H., Monge P., García M., Mergler D. Chronic nervous-system effects of long-term occupational exposure to DDT. Lancet. 2001 Mar 31;357(9261):1014–1016. doi: 10.1016/S0140-6736(00)04249-5. [DOI] [PubMed] [Google Scholar]

Articles from Environmental Health Perspectives are provided here courtesy of National Institute of Environmental Health Sciences

RESOURCES