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Biomedical subjects

S P Kirychuk

Publications and source records attributed to S P Kirychuk.

7 recordsLinked to original sources

Respiratory response to endotoxin and dust predicts evidence of inflammatory response in volunteers in a swine barn.

BACKGROUND: It has been shown that exposure in intense exposure in swine barn facilities is associated with increased respiratory symptoms and reduction in pulmonary functions. This study investigated if systemic response could be predicted by FEV(1) response following swine barn exposure. METHODS: Naïve males were tested at baseline, low and high endotoxin and dust levels. Subjects were classified as "more responsive" (n = 9) or "less responsive" (n = 11) based on FEV(1) reduction following high endotoxin exposure. Health measures included pulmonary function testing, blood samples and nasal lavage. Environmental samples were collected from the barn. RESULTS: White blood cells and blood lymphocytes at low exposure were significantly greater in those who were "more responsive" compared to those who were "less responsive". There was a significant increase in blood lymphocytes, serum IL6, total nasal lavage cells and nasal IL8 at high exposure among "more responsive" subjects compared to "less responsive" subjects. CONCLUSIONS: Respiratory response to high-level endotoxin and dust exposure predicts evidence of inflammatory response throughout a range of endotoxin and dust exposures.

Adolescent↗

Total dust and endotoxin in poultry operations: comparison between cage and floor housing and respiratory effects in workers.

OBJECTIVE: The objective of this study was to assess respiratory outcomes and environmental exposure levels of workers in cage-housed and floor-housed poultry operations. METHODS: Poultry operations were evaluated for total dust, endotoxin, and ammonia, and respiratory symptoms and lung function tests of workers were conducted. RESULTS: Workers in floor-housed poultry operations had significantly greater exposures to total dust and ammonia, whereas workers from cage-housed poultry operations reported greater frequency of current and chronic symptoms overall and significantly greater current and chronic phlegm (39% vs 18% and 40% vs 11%, respectively). Endotoxin concentration (EU/mg) was a significant predictor (P = 0.05) of chronic phlegm for all poultry workers. CONCLUSIONS: Greater endotoxin concentration in the presence of significantly lower total dust, in conjunction with greater respiratory symptoms in workers from cage-housed poultry operations, as compared with workers from floor-housed poultry operations, appears to indicate that differences in environmental exposures may impact respiratory outcomes of workers.

Adult↗

Occupational asthma in newly employed workers in intensive swine confinement facilities.

Respiratory symptoms, reductions in pulmonary function and increased bronchial responsiveness have been described in exposed workers and in naïve volunteers exposed to intensive swine production facilities. Typically, this occurs in persons who have been employed for a long duration or in previously unexposed, naïve volunteers. The current authors describe four cases, all female, who developed acute onset of wheezing and cough suggestive of asthma within weeks of commencing full-time employment in intensive swine production facilities. None of the workers were aware of any previous asthma, allergies or hay fever. All four employees reported improvement of symptoms on cessation of work in the facilities and consequent withdrawal from exposure. However, when seen at the respiratory clinic, cases 1 and 3 continued to be either mildly symptomatic or were taking medications with continued borderline airways responsiveness, as measured by methacholine challenge test up to 4 and 5 months, respectively, following work cessation. Case 2 continued to have symptoms for > or =3 months after work cessation. Only case 1, however, was seen at repeated visits in the respiratory clinic. One worker participated in a work re-entry trial and experienced profound coughing and chest tightness within an hour of entry, after which, the trial had to be terminated. Provocative concentration causing a 20% fall in forced expiratory volume in one second (PC20) measured 5 h later was lower than pre-trial PC20. No acute exposure event was recorded in the workers prior to the onset of symptoms. To the current authors' knowledge, this is the first report of occupational asthma occurring in newly employed full-time intensive swine production workers after a short-term exposure and should raise awareness that previously unexposed workers may be at risk of developing what would appear to be long-term asthma after relatively short-term exposure.

Adult↗

Positive human health effects of wearing a respirator in a swine barn.

STUDY OBJECTIVES: A study was conducted to evaluate the acute health effects of wearing an N-95 disposable respirator in a swine confinement facility. DESIGN: A crossover trial design was used in the study. SETTING: The study was carried out at the research facilities of the Centre for Agricultural Medicine, the Royal University Hospital, and the Prairie Swine Centre Inc, Saskatoon, Saskatchewan, Canada. PARTICIPANTS: Twenty-one nonsmoking healthy male subjects with no previous swine barn exposure participated in the study. INTERVENTIONS: The subjects participated in a laboratory session (baseline day), a 4-h exposure in a traditional swine room wearing the respirator (intervention day), and a 4-hour exposure in a traditional swine room without a respirator (nonintervention day). MEASUREMENTS: Lung function, methacholine challenge tests, blood counts, nasal lavage, and cytokines in serum and nasal lavage fluid. RESULTS: Mean (+/- SE) shift change in FEV(1), from preexposure to postexposure, was highest on nonintervention day (-8.1+/-1.01%) and was significantly different from intervention day (0.32+/-0.62%; p<0.0001) and baseline day (1.57+/-0.51%; p<0.0001). Similar patterns were observed in the mean values of the provocative concentration of a substance (methacholine) causing a 20% fall in FEV(1) (nonintervention day, 130.4+/-36.9 mg/mL; intervention day, 242.0+/-38.0 mg/mL; and baseline day, 328.0 mg/mL +/-34.1 mg/mL). Significant increases in serum neutrophil levels and nasal cell counts were observed on the nonintervention day in comparison to the baseline and intervention days. Significant increases also were found in the levels of cytokines interleukin (IL)-6 and IL-8 in nasal lavage fluid and in the levels of IL-6 in serum for the nonintervention day in comparison to the other 2 days. CONCLUSIONS: The results demonstrate that an N-95 disposable respirator can help to significantly reduce acute negative health effects in subjects not previously exposed to a swine barn environment.

Adolescent↗

Positive human health effects of dust suppression with canola oil in swine barns.

A crossover trial was conducted to evaluate the acute human health effects of a dust control technology in a swine confinement facility. Twenty lifetime nonsmoking male subjects, with no evidence of allergy or asthma and no previous swine barn exposure, participated in the study, which included a laboratory session (baseline), 5-h exposure in a swine room sprinkled with canola oil (treatment) and 5-h exposure in a traditional swine room (control). Mean values of inhalable dust concentrations and endotoxin levels in the control room were significantly greater than those observed in the treatment room. Mean shift changes in FEV1 from preexposure to end of exposure were 1.1% (standard error, 0.63%) on baseline day, -1.9% (0.63%) on treatment day, and -9.9% (1.12%) on control day; the differences in the shift changes were statistically significant. Mean value of methacholine concentration that reduced the FEV1 by 20% (PC20) in bronchoprovocation tests on baseline day was significantly different from that on treatment day (p = 0.04) and that on control day (p < 0.001). Significant increases were also observed in white blood cell counts and nasal lavage cell counts on the control day in comparison with the other two days. Blood neutrophil counts after control room exposure were twice those observed on baseline and after exposure to the treatment room. Significant differences were also observed in IL-1 beta, IL-6, and IL-8 nasal lavage cytokines and in IL-6 serum cytokine. These results suggest that the canola oil dust control method is effective in improving indoor air quality in swine barns and reducing acute health effects in naive healthy subjects.

Adolescent↗

Accelerated lung function decline in swine confinement workers.

We conducted a longitudinal study to determine the annual rate decline in pulmonary function measurements in male swine confinement workers. For comparison, a grain farming group and a nonfarming rural-dwelling control group were also chosen for the longitudinal study. Two hundred seventeen swine confinement workers, 218 grain farmers, and 179 nonfarming control subjects had valid pulmonary function measurements at the baseline observation conducted in 1990 to 1991 and at the second observation conducted in 1994 to 1995. The swine confinement workers were younger (mean age=38.3+/-11.7 [SD] years) than the nonfarming control subjects (42.6+/-10.4 years) and the grain farmers (44.5+/-11.9 years). When stratified by age, nonfarming control subjects had the lowest mean annual rate decline in FEV1 and FVC in all age categories. The swine confinement workers had the largest annual rate decline in FEV1 and FVC, and this was most obvious in the middle age categories. After controlling for age, height, smoking, and baseline pulmonary function, swine confinement workers had excess annual decline of 26.1 mL in FEV1 (p=0.0005), 33.5 mL in FVC (p=0.0002), and 42.0 mL/s in forced expiratory flow between 25% and 75% of FVC (FEF[25-75%]) (p=0.02) over nonfarming control subjects. Grain farmers had excess annual decline of 16.4 mL in FEV1 (p=0.03), 26.7 mL in FVC (p=0.002), and 11.2 mL/s in FEF(25-75%) (p=0.38) over control subjects. These findings suggest that workers engaged in the swine industry and grain farmers appear prone to accelerated yearly losses in lung function and may therefore be at risk for the future development of chronic airflow limitation.

Adult↗