Detection and Measurement of Unhealthy, Environment-Derived Aerosol Materials in an Emergency Department

OBJECTIVE

To measure unhealthy aerosol materials in an Emergency Department (ED) and identify their sources for mitigation efforts.

BACKGROUND

Based on pilot findings of elevated ED particulate matter (PM) levels, investigators hypothesized that unhealthy aerosol materials derive from exogenous (vehicular) sources at ambulance receiving entrances.

METHODS

The Aerosol Environmental Toxicity in Healthcare-related Exposure and Risk program was conducted as an observational study. Calibrated sensors monitored PM and toxic gases at Ambulance Triage Exterior (ATE), Ambulance Triage Desk (ATD), and control Public Triage Desk (PTD) on a 3/3/3-day cycle. Cassette sampling characterized PM; meteorological and ambulance traffic data were logged. Descriptive and multiple linear regression analyses assessed for interactions between aerosol material levels, location, temporal variables, ambulance activity, and meteorological factors.

RESULTS

Sensors acquired 93,682 PM0.3, 90,250 PM2.5, and 93,768 PM5 measurements over 366 days to generate a data set representing at least 85.6% of planned measurements. PM0.3, PM2.5, and PM5 mean counts were lowest in PTD; 56%, 224%, and 223% higher in ATD; and 996%, 200%, and 63% higher in ATE, respectively (all p < .001). Qualitative analyses showed similar PM compositions in ATD and ATE. On multiple linear regression analysis, PM0.3 counts correlated primarily with location; PM2.5 and PM5 counts correlated most strongly with location and ambulance presence. PM < 2.5 and toxic gas concentrations at ATD and PTD patient care areas did not exceed hazard levels; PM0.3 counts did not have formal safety thresholds for comparison.

CONCLUSIONS

Higher levels of PM were linked with ED ambulance areas, although their health impact is unclear.

Role of sulfate conjugation in estrogen metabolism and activity

There has been an increasing interest in the sulfate conjugates of estrogens as important metabolites in steroid hormone homeostasis and activity. In women estrogen sulfates have been known as major components of plasma originating from ovarian secretion and hepatic metabolism. However, only recently has the capacity to sulfurylate estrogens been demonstrated in estrogen target tissues. Porcine uterus estrogen sulfotransferase appears only after the first complete estrous cycle. Following puberty, gilt uterine sulfurylation of estrogens is extremely active during diestrus, whereas estrogen sulfotransferase is not present during estrus. This cycling of estrogen sulfurylation in porcine and human uteri can be related directly to plasma progesterone levels. Rodent and human mammary tumors are also highly active in both steroid alcohol and estrogen sulfotransferases. Unlike uterine sulfotransferases, these enzymes are apparently stimulated by factors that appear following ovariectomy. The function of estrogen sulfurylation by target tissues remains obscure. However, recent investigations have indicated that the cyclic variation in endometrial estrogen sulfurylation may control the availability of 17 beta-estradiol to the cytoplasmic receptor. This premise is supported by the continued high estrogen sulfurylation activity and low nuclear receptor levels during implantation in fertilized gilts and sows. Utilizing purified bovine adrenal sulfotransferase, the substrate and inhibitor requirements were determined for this enzymes. It was also possible to design a specific inhibitor that will block estrogen sulfurylation without interfering with the receptor binding and nuclear migration of physiological levels of 17 beta-estradiol. This inhibitor, 3-methoxy-4-nitroestrone, will help in establishing the role of uterine and mammary estrogen sulfurylation.

The steroid alcohol and estrogen sulfotransferases in rodent and human mammary tumors

Rodent and human mammary tumor systems were investigated to relate the steroid alcohol and estrogen sulfotransferase activities to the hormoanl dependency of the tumor as determined by estrogen receptor content. Unlike the normal mammary gland or the hyperplastic alveolar nodule, rodent mammary neoplasms displayed significant levels of these two sulfotransferases. In the hormone-independent mouse tumors produced from out-growth lines D1, D2, and D8, high dehydroepiandrosterone sulfotransferase activity was characteristic of the rapidity with which hyperplastic alveolar nodules developed into a neoplasms (V-max = 52.8 versus 1.8 fmoles/min/mg protein) while estrone sulfotransferase activity was either not detectable or low (V-max = 5.5 fmoles). After oophorectomy of mice bearing slowly developing tumors, both sulfotransferases in the nonregressing neoplasms showed marked increases in activity (V-max dehydroepiandrosterone = 30.0 fmoles; V-max estrone = 18.5 fmoles). Strain differences not the estrogen receptor content of hormone-dependent rat mammary tumors. In Wistar-Lewis rats the steroid alcohol sulfotransferase activity was at least 35 times higher than in the Sprague-Dawley strain. As was observed in the mouse mammary tumor, Sprague-Dawley rat neoplasms that grew in the absence of ovarian hormones contained significantly greater levels of the steroid alcohol sulfotransferase. Possible correlaion between presence of the steroid alcohol sulfotransferase and the estrogen receptor protein was observed in a limited number of human breast carcinomas.