RESEARCH PAPER
Health effects of selected microbiological control agents. A 3-year follow-up study
 
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1
Department of Occupational and Environmental Medicine, Odense University Hospital, Denmark
2
Medical Department, Fredericia Hospital, Denmark
3
Institute of Risk Assessment, University of Utrecht, the Netherlands
4
Department of Environmental and Occupational Medicine, Institute of Public Health, Aarhus University, Denmark
CORRESPONDING AUTHOR
Jesper Baelum   

Department of Occupational and Environmental Medicine, Odense University Hospital, Denmark
 
Ann Agric Environ Med. 2012;19(4):631–636
KEYWORDS
ABSTRACT
Introduction and objectives:
Microbiological control agents (MBCA) are widely used in greenhouses, replacing chemical pesticides. The presented study aims to describe health effects of exposure to three types commonly used: Bacillus thuringiensis, Verticillium lecanii, and Trichoderma harzenianum covering seven different products in greenhouse workers with emphasis on sensitization and respiratory effects.

Methods:
579 persons aged 17-67 years culturing ornamental flowers were included. They were followed for three years with annual examinations including interview about exposure and symptoms, lung function, including bronchial (histamine) challenge test, and blood samples. Direct and indirect exposure for each person and year was estimated by information from respondents and employers. IgE in serum against the 7 products of MCBA was analyzed using an enzyme immunoassay technique.

Results:
65%, 40%, and 78% were exposed to B. thuringiensis, V. lecanii and T. harzenianum, respectively, while 6, 3 and 3% were handling the products. IgE against B. thuringiensis was seen in 53% of the samples and with prevalence rate ratios among exposed increasing from 1.20 (CI95%:1.01-1.42) to 1.43 (CI95%:1.09-1.87) over the 3-year period. There was no relation between exposure to any MBCA and neither prevalence nor incidence of respiratory symptoms and there was no effect on lung function or bronchial responsiveness.

Conclusions:
Use of B. thuringiensis in greenhouses may give rise to sensitization while no effect on the occurrence of respiratory symptoms or lung function was observed. The persons had a relatively long exposure. Therefore, a healthy worker effect may have influenced the results.

 
REFERENCES (19)
1.
Bravo A, Gill SS, Soberon M. Mode of action of Bacillus thuringiensis Cry and Cyt toxins and their potential for insect control. Toxicon. 2007; 49(4): 423-435.
 
2.
Microbial Pest Control Agent BACILLUS THURINGIENSIS 1999, World Health Organization. Geneva.
 
3.
Jensen GB, Larsen P, Jacobsen BL, Madsen B, Smidt L, Andrup L. Bacillus thuringiensis in fecal samples from greenhouse workers after exposure to B-thuringiensis-based pesticides. App Environ Microbiol. 2002; 68(10): 4900-4905.
 
4.
Bernstein IL, Bernstein JA, Miller M, Tierzieva S, Bernstein DI, Lummus Z, Selgrade MK, et al. Immune responses in farm workers a er exposure to Bacillus thuringiensis pesticides. Environ Health Perspect. 1999; 107(7): 575-582.
 
5.
Doekes G, Douwes J, Wouters I, de Wind S, Houba R, Hollander A. Enzyme immunoassays for total and allergen specific IgE in population studies. Occup Environ Med. 1996; 53(1): 63-70.
 
6.
Eaton KK, Hennessy TJ, Snodin DJ, McNulty DW. Verticillium lecanii. Allergological and toxicological studies on work exposed personnel. Ann Occup Hyg. 1986; 30(2): 209-217.
 
7.
Davies PD, Jacobs R, Mullins J, Davies BH. Occupational asthma in tomato growers following an outbreak of the fungus Verticillium albo-atrum in the crop. J Soc Occup Med. 1988; 38(1-2): 13-17.
 
8.
Chouaki T, Lavarde V, Lachaud L, Raccurt CP, Hennequin C. Invasive infections due to Trichoderma species: Report of 2 cases, findings of in vitro susceptibility testing, and review of the literature. Clinical Infect Dis. 2002; 35(11): 1360-1367.
 
9.
Das S, Gupta-Bhattacharya S. Trichoderma harzianum: occurrence in the air and clinical significance. Aerobiologia 2009; 25(3): 137-145.
 
10.
Kogevinas M, Anto M, Sunyer J, Tobias J, Kromhout A, Burney H, et al. Occupational asthma in Europe and other industrialised areas: a population-based study. European Community Respiratory Health Survey Study Group. Lancet 1999; 353(9166): 1750-1754.
 
11.
Monsó E, Magarolas R, Badorrey I, Radon K, Nowak D, Morera J. Occupational asthma in greenhouse flower and ornamental plant growers. Am J Respir Crit Care Med. 2002; 165(7): 954-960.
 
12.
Dansk Lungemedicinsk S. SPIROMETRI – en rekommandation. J Thuesen Pedersen, et al., Editors. Nationalforeningen til bek‘mpelse af Lungesygdomme: Kobenhavn. 1996: 1-17.
 
13.
Omland Ø, Sigsgaard T, Hjort C, Pedersen OF, Miller MR. Lung status in young Danish rurals: the effect of farming exposure on asthma-like symptoms and lung function. Eur Respir J. 1999; 13(1): 31-37.
 
14.
Yan K, Salome C, Woolcock AJ. Rapid method for measurement of bronchial responsiveness. Thorax 1983; 38(10): 760-765.
 
15.
Pekkanen J, Burney P, Sunyer J, Anto JM. Operational definitions of asthma in studies on its aetiology. Eur Respir J. 2005; 26(1): 28-35.
 
16.
Jensen GB, Larsen P, Jacobsen BL, Madsen B, Wilcks A, Smidt L, Andrup L. Isolation and characterization of Bacillus cereus-like bacteria from faecal samples from greenhouse workers who are using Bacillus thuringiensis-based insecticides. Int Arch Occup Environ Health. 2002; 75(3): 191-196.
 
17.
Barfod KK, Poulsen SP, Hammer M, Larsen ST. Sub-chronic lung inflammation after airway exposures to Bacillus thuringiensis biopesticides in mice. BMC Microbiol. 2010; 10: 233.
 
18.
Loschenkohl B. Thygesen K, Nielsen SL. Måling af bioaerosoler under udbringning af mikrobiologiske bekæmpelsesmidler og ved e erfølgende arbejdsprocesser i potteplanter (Measurement of bioaerosols during application of microbiological pesticides and during subsequent work processes). Danish EPA Bekæmpelsesmiddelforskning, nr. 79 2003. (in Danish).
 
19.
Meyer HW, Jensen KA, Nielsen KF, Kildesø J, Norn S, Permin H, et al. Double blind placebo controlled exposure to molds: exposure system and clinical results. Indoor Air. 2005; 15 Suppl 10: 73-80.
 
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