87
GRAVIMETRIC AND ENDOTOXIN EVALUATION OF SIZE-SELECTIVE SAMPLING METHODS USING
SWINE DUST IN A WIND TUNNEL.
S. Reynolds, J. Nakatsu, J. Mehaffy, M. Tillery, T. Keefe, Colorado State University, Ft. Collins, CO; P. Thorne, M. O’Neill, N. Metwali, P. O’Shaughnessy, University of Iowa, Iowa City, IA.
The performance of five gravimetric methods for measuring agricultural dusts [total dust (37-mm cassette), respirable dust (cyclone), inhalable (IOM), inhalable (IOM) with size-selective MultiFoam disc, and Button] was evaluated using swine dust in a wind tunnel. Twenty sessions were conducted, velocities of 0.2 and 1.0 m/s. Pairs of samplers were attached to a rotating mannequin to cancel directional effects. Samples were analyzed for endotoxin using the Recombinant Factor C (rFC) and Kinetic LAL assays. At 1.0 m/s, consistent relationships were found for total dust, cyclone, and IOM multifoam inhalable portion (r = 0.508–0.552, p = 0.012–0.022). The IOM correlated with both inhalable and respirable fractions of the IOM with multifoam (r = 0.49, 0.51, p = 0.048, 0.022). At 0.2 m/s, the total dust and cyclone were correlated (r = 0.680, p = 0.001). The IOM correlated with both inhalable and respirable multifoam disc samples (r = 0.458, 0.534, p = 0.042, 0.015). The rFC and Kinetic LAL assays correlated well (r = 0.49, p < 0.001). There appears to be a trend in the endotoxin content of the swine dust, with lower stages of the cascade impactor (cut point < 2.8 microns) containing about half the EU/mg of upper stages. ANOVA confirmed differences in EU/mg content of the size selective sampling devices. The respirable fraction of the IOM always contained lower EU/mg than other devices. Endotoxin content of the cyclone was not statistically different from the total dust, Button, or IOM inhalable fraction. However, the IOM without the foam insert yielded lower EU/mg than the total and respirable samplers. Unlike studies with Arizona Road Dust, these data suggest that wind speed may not be the sole determining factor affecting sampler performance. Differences in endotoxin content by aerosol size may have implications for respiratory disease.
88
PERSONAL EXPOSURE TO TOTAL DUST, AMMONIA, AND ENDOTOXIN AMONG WORKERS IN A SWINE
CONFINEMENT FACILITY.
R. Malcolm, L. Conroy, T. Schoonover, S. Erdal, University of Illinois at Chicago, Chicago, IL.
A study was conducted to evaluate workers’ exposure to total dust, ammonia, and endotoxin in a swine confinement facility located in central Illinois. This facility housed approximately 17,000 pigs. Personal samples of total dust, ammonia, and endotoxin were collected over a two-day period. Seven of eight workers were sampled on Day 1 and five of eight workers were sampled on Day 2. Five University of Illinois at Chicago (UIC) observers were sampled on both days. Two 37-mm cassette filters connected to a single pump using a Y connector were used to sample for total dust and endotoxin, respectively. Ammonia was collected using a passive sampler attached to the worker. Overall total dust concentrations ranged from 0.077–8.15 mg/m3 (mean = 2.88 mg/m3). The total dust concentrations for swine confinement workers ranged from 0.359–5.77 mg/m3 (mean = 3.31 mg/m3), whereas the total dust concentrations for UIC observers ranged from 0.077–8.15 mg/m3 (mean = 2.26 mg/m3). Ammonia concentrations ranged from 2.79–16.8 ppm (mean = 8.74 ppm) for all participants. Ammonia concentrations for swine confinement workers ranged from 5.60–16.8 ppm (mean = 9.24 ppm), whereas ammonia concentrations for UIC observers ranged from 5.82–10.3 ppm (mean = 8.16 ppm). Endotoxin concentrations ranged from 316–8435 EU/m3 (mean = 2425 EU/m3) for all participants. Endotoxin concentrations ranged from 316–8036 EU/m3 (mean = 2107 EU/m3) and from 323–8435 EU/m3 (mean = 2732 EU/m3) for swine confinement workers and UIC observers, respectively. The TLV for nuisance dust was not exceeded; however, this is not a valid comparison. Based on previous studies it has been shown that dust generated in a swine confinement facility is an organic dust not nuisance dust. The TLV of 25 ppm for ammonia was not exceeded; however, the highest concentration is greater than half the TLV. Based on previous studies the highest endotoxin concentration (8435 EU/m3) would not be considered a high concentration for workers in a swine confinement facility.
89
THE EFFECTS OF ENVIRONMENTAL IMPROVEMENT ON THE BIOAEROSOL CONCENTRATIONS IN THE
LAYER HOUSES.
W. Lin, W. Tian, W. Chang, Y. Weng, C. Ho, C. Chen, Chung Shan Medical University, Taichung, Taiwan Republic of China; W. Chou, Hung Kuang University, Salu, Taichung, Taiwan Republic of China.
The bioaerosol concentrations in the layer houses would be as high as 106 CFU/m3, where the environment control should be needed. In order to evaluate the effect of the environmental improvement, the bioaerosol concentrations were measured before and after the improvement at two layer houses in central Taiwan, with 15,000 and 20,000 layers, respectively. For each sampling day, four sequential bioaerosol samples were collected by the AGI-30 all-glass impingers at the flow rates of 12.5 L/min, and tryptic soy agar (Scharlau) and malt extract agar (Difco) were selected to recover bacterial and fungal colonies, respectively. In the first layer house, the fungal concentrations before improvement were found to be 1.98×104, 8.25×104, and 4.99×105 CFU/m3 for the three sampling days, respectively. After the improvement, the fungal concentrations were found to be 3.13×102, 1.43×103, and 3.31×103 CFU/m3, respectively. In the second layer house, the fungal concentrations before improvement were found to be 8.94×103, 1.76 ×105, and 13.4×105 for the three sampling days, respectively. After the improvement, the fungal concentrations were found to be 1.31×103, 8.57×103, and 8.58×103 CFU/m3, respectively. In the first layer house, the airborne bacterial concentrations before improvement were found to be 1.24×105, 3.35×105, and 7.54×104 CFU/m3 for the three sampling days, respectively. After the improvement, the bacterial concentrations were found to be 3.78×104, 4.91×104, and 2.79×104 CFU/m3, respectively. In the second layer house, the bacterial concentrations before improvement were found to be 2.42×105, 5.90×104, and 1.12×105 CFU/m3 for the three sampling days, respectively. After the improvement, the bacterial concentrations were found to be 5.41×104, 3.39×104, and 2.46×104 CFU/m3, respectively. The results demonstrated that the fungal and bacterial bioaerosol concentrations in the layer houses decreased after the environmental improvement.
90
AN OVERVIEW OF CLOSED SYSTEM USE FOR PESTICIDES IN CALIFORNIA, 2001–2002.
H. Fong, F. Schneider, Cal/EPA, Sacramento, CA.
The California Department of Pesticide Regulation conducted a survey of sealed pesticide transfer devices (closed systems) in use between 2001 and 2002. The use of closed systems has been a regulatory requirement since the late 1970s. Since a standard design was not promulgated, there have been various attempts to fulfill the requirements found in the “Director’s Criteria for Closed Systems.” Closed systems allow for the sealed transfer of pesticides from their original container into mixing equipment, then into application equipment.
Three major systems were identified: suction extraction, container breach, and direct drop/gravity feed. Suction extraction depends on vacuum removal of container contents. Container breach utilizes slicing or spearing actions to puncture containers. Direct drop/gravity feed allows the container to be directly connected atop the mixing tank and use gravity to empty into the tank.
The closed systems were surveyed as to their compliance with the Director’s criteria. The system users were also queried as to problems encountered. Most of the systems surveyed met the criteria. However, there was a general set of problems identified. These problems were: nonstandardized container interfaces; problems with container rinsing; measuring difficulties; and system complexities.
The nonstandardized container interfaces and
container rinsing problems are interrelated, since in both cases removal of
either the concentrate or the pesticide-contaminated rinsate is by the same
means. Fine measurement is likewise difficult, especially with container breach
systems.
Complexity problems often arise from inadequately trained or untrained personnel
(i.e., emergency responders). Under these conditions, the lack of posted
instructions and unidentified control and flow systems could cause unsafe
conditions. A standard opening interface requirement may resolve many of the
problems. Better identification of hose contents, valve operation, and the
posting of emergency shutdown procedures could address the problems of conduit
and valve identification and emergency shutdown.
91
OCCUPATIONAL EXPOSURES TO NOISE IN AGRICULTURAL SETTINGS.
C. Achutan, R. Tubbs, CDC/NIOSH, Cincinnati, OH.
Agricultural workers are exposed to excessive noise levels on a routine basis. However, there are limited data in the scientific literature characterizing the occupational noise exposures to agricultural workers. This abstract discusses two health hazard evaluations conducted by the National Institute for Occupational Safety and Health (NIOSH) in three agricultural settings. Personal dosimetry was collected on employees at a swine confinement, a potato processing, and an alfalfa manufacturing facility. Area noise measurements were also taken throughout these three facilities.
At the swine confinement facility, all seven dosimeter samples were below the OSHA permissible exposure limit. However, the potential for high noise exposures is evident in the noise dose of specific short-term activities such as power washing of barns and during snout snaring and ear clipping. At the potato processing and alfalfa manufacturing operations, five of 20 employees who were monitored attained or exceeded the NIOSH REL. Two of them also exceeded the OSHA AL. The highest noise exposure at the potato processing plant was to the employees who bag potatoes in sacks. At the alfalfa pellet manufacturing area, it was the operator of the pellet mill who had the highest exposure. Area measurements taken in all three facilities supported the high noise levels observed with personal dosimetry.
At the swine confinement facility, NIOSH investigators recommended that employees be enrolled in a hearing conservation program, properly maintain their hearing protection devices, and replace or pad some of the metal pieces with softer material to prevent metal-to-metal contact. At the potato processing plant, NIOSH investigators offered assistance in choosing hearing protection devices that may improve communication between employees. At the alfalfa pellet operation, NIOSH investigators recommended that the pellet mill operator be enrolled in a hearing conservation program and limit the time spent outside the control booth.
92
PARTICIPATORY APPROACH IN OCCUPATIONAL HEALTH OF HISPANIC FARMWORKERS IN THE
“LAKE REGION.”
M. Vela Acosta, University of Texas, Brownsville, TX; V. Fischer, D. Reding, Marshfield Clinic, Marshfield, WI; S. Cooper, Texas A & M University, Bryan, TX.
Background. Innovative models that incorporate participatory research to reduce the occupational risk for a seasonal farmwork force require regional partnerships. Interventions in states not traditionally known for large Hispanic populations place distinctive challenges on services not designed for Spanish-speaking workers. Methods. A practical occupational health assessment of agricultural sites in the “Lake Region” (Wisconsin, Michigan, and Minnesota) was conducted. Selective on-site safety audits (n = 7) assessed agricultural employers’ and farmworkers’ safety risks and needs in the three states. The incidence of occupational health outcomes of farmworkers during that agricultural season was estimated through examination of clinical health records of farmworkers in Wisconsin. All information gathered from agricultural employers, health records, and farmworkers was used to determine the effectiveness for this intervention. Results. Main hazards found during the on-site audits were ergonomic risk factors, field sanitation, insect bites, and lack of Spanish bilingual training materials. Incidence rates of nonfatal occupational injury and lost workday cases exceeded the national average at one Christmas tree operation by almost seven times. At the migrant health clinic of Wisconsin, 21% of the farmworkers’ medical visits (284 out of 1368) were due to occupational related problems, with the highest incidence for musculoskeletal diseases. Conclusions. This participatory approach, which included agricultural employers, migrant agencies, and researchers, demonstrated potential to benefit the occupational health and safety of farmworkers in the Lake Region through enhanced resources and services. Additional research efforts are required to implement this approach to a wider range of agricultural employer sites.
Posted May 30, 2005