Search

Highlights • A customized exposure chamber was used to measure the particulate respirator efficiency of NIOSH-certified respirators and home-made respirators. • The chamber was validated using P100 and N95 respirators. • Custom-made respirators fabricated from Halyard® H600 sterilization fabric material were claimed as N95 alternative with superior efficiency. • The results indicated that the Halyard® H600 sterilization fabric has lower filter efficiency compared to P100 and N95, and is not recommended for use as an alternative for the N95 respirator., Background Due to COVID-19 and high demand for respirators, some healthcare professionals have been using the Halyard H600 fabric as an alternative to N95 respirators without testing the filtration efficiency of the fabric with established scientific methods. The purpose of this study was to assess the efficiency of the Halyard H600 as a respirator filtering material as compared to the NIOSH-certified N95 and P100 filters, and determine if H600 is a good alternative for respiratory protection for healthcare professionals during the COVID-19 pandemic. Methods Three filter types (Halyard H600, N95 and P100) were challenged with salt particles inside an exposure chamber at a flow rate of 43 LPM and relative humidity of 40±2%. N95 and P100 respirator filters were tested initially to establish the validity of the chamber, followed by the Halyard H600 fabric. Particle penetration was measured using an aerosol spectrometer. The filtration efficiency was calculated for different particle sizes by measuring the particle number concentration upstream and downstream of the filter. The pressure drop across the filter materials was measured using a manometer. Results The efficiency of the P100 for particles ≥250 nm was 100%. The N95 efficiency was 97±1% at 275 nm, 99±0% at 324 nm, and 100% for larger particles. The Halyard H600 fabric had a variable efficiency with an average of 62±28% at 275 nm, 89±8% at 324 nm, and 100% efficiency for particles >450 nm. The pressure drop values for P100 and N95 were 32 and 8 mmH20, respectively. The Halyard H600 fabric resistance increased dramatically from 30 mmH20 at the start of the exposure to 65 mmH20 after 16-min of exposure. Conclusion The high variability in filter efficiency for particles ≤324 nm and the increased fabric breathing resistance demonstrate that the Halyard H600 has an inferior performance and is not a good substitute for N95 and P100. Thus, the use of the Halyard H600 fabric for respiratory protection is not recommended.

Little is known about risk factors associated with poor health among employees with COPD living in Central Appalachia. Purpose: Determine variability in health distress based on risk factors, inclu...

Mosquitoes can be a nuisance and can transmit pathogens causing numerous diseases. Homeowners may hire private companies that use barrier sprays to alleviate mosquito-related issues, especially in areas where government funding for mosquito control programs is limited. Here, the spatial distribution of mosquitoes was evaluated in a suburban neighborhood during successive treatments with either Bifen Insecticide/Termiticide (active ingredient: bifenthrin) or Suspend Polyzone (active ingredient: deltamethrin) from May 17 to November 8, 2016. A total of 15,083 adult mosquitoes and 18,054 mosquito eggs were collected. Analysis of variance (P < 0.05) was used to analyze differences in abundance of key species between weeks, traps, and treatments. Weather trends were analyzed in relation to mosquito abundance using time-lagged weekly average temperatures and total rainfall. Kriging showed hot spots of mosquito abundance. The spatial pattern of abundance was different for oviposition and adults, and this was expected because of different types of traps used here. A land cover analysis was performed within the geographic information system (GIS) file to determine the extent to which land cover type could predict mosquito abundance. We show an uneven distribution of host-seeking mosquito abundance and that, in general, mosquitoes preferred areas that were lightly wooded or composed of small collections of trees or bushes, compared with larger densely wooded areas. Analyses of spatial distribution, land cover, and weather can be used to supplement an integrated mosquito management approach.

Adults who work in the Central Appalachian region of the United States (U.S.) are disproportionately affected by Chronic Obstructive Pulmonary Disease (COPD). While there is a socio-demographic profile of adults with COPD who are at increased risk for physical and mental distress, the risk factors that uniquely affect the health-related quality of life (HRQoL) of Central Appalachian workers with COPD are unknown. Therefore, we conducted a latent class analysis of 2016 and 2017 Behavioral Risk Factor Surveillance System data from 1326 currently employed adults with COPD living in four U.S. states (KY, NC, TN, and WV) within the Central Appalachian Region. Drawing from the social ecological model, we identified associations between theoretically informed risk indicators&mdash, comorbid health conditions, substance use and abuse, and limited access to healthcare&mdash, on three HRQoL variables, including infrequent (0&ndash, 13 days) or frequent (&ge, 14 days) physical distress, mental distress, and limited activity due to poor health over the past 30 days. Workers at high risk for comorbid conditions reported more frequent physical distress, mental distress, and activity limitations as compared to those at low risk. Workers reporting difficulty accessing healthcare were no more likely to report physical or mental distress when compared to workers with adequate access to healthcare, however, those with limited healthcare access did report more frequent activity limitation due to poor health. Interestingly, workers with COPD at high risk for substance use and abuse were no more likely to report poor HRQoL outcomes compared to those at low risk. Our findings have important implications for addressing indicators of poor health among Central Appalachian workers with COPD, especially those living with multiple comorbidities.

Ants, bees, hornets, wasps, and yellow jackets (insects in Order Hymenoptera) are potentially a serious concern to outdoor workers, as the venom from their stings can cause life-threatening allergic reactions. This study assessed the impacts of Hymenoptera stings and related worker training regimes of forestry workers across the United States (US).A survey was distributed to nearly 2,000 outdoor workers in the forestry industry from four US regions (South, West, Northeast, and Midwest).Ants are a primary concern in the South, with75% of participants reporting ant stings within the last 5 years. Bees, hornets, wasps, and yellow jackets are a concern for surveyed foresters in all US regions, with 60-70% and 75-93% of participants, respectively, having been stung by bees or hornets/wasps/yellow jackets within the last 5 years. Despite such a large number of participants experiencing stings, nearly 75% of participants were not concerned about being stung or their reaction to stings. Approximately, 70% of participants reported not having received any safety training related to Hymenoptera from their employers.No significant difference was shown in the number of foresters stung at work between safety trained and non-safety trained participants. However, it was significantly more likely for participants to carry a first aid kit if they had received Hymenoptera safety training. Consequently, more comprehensive and frequent training should be considered to help reduce risk of exposure to Hymenoptera.

Minimizing arthropod exposure (e.g. mosquito and tick bites) is vital to protect health of outdoor workers. Personal protective measures can help protect against exposure. Here, the quantity of permethrin was evaluated for different fabric types after washing. Cone and petri dish exposure assays were used to investigate the knockdown/mortality of permethrin-susceptible and permethrin-resistant populations of mosquitoes. Permethrin-treated clothing was effective against the tested mosquito population that was susceptible to permethrin but not a permethrin-resistant population. Permethrin quantity was significantly highest in the 100% cotton fabric and for the 0 wash group. Permethrin quantity in fabrics decreased with washing. No significant differences (p > 0.05) were observed in knockdown/mortality rates for either exposure method. The protective effect of permethrin-treated clothing against mosquitoes is impacted by many factors, e.g. wash frequency, fabric type, and the susceptibility/resistance status of local mosquito populations.

Mosquitoes exposed to sublethal doses of insecticides may be selected for resistance to insecticide active ingredients (AIs). Mosquitoes are exposed to AIs through agricultural, public/private mosquito control programs, homeowners, and other sources. Hence, mosquito control programs should routinely measure the resistance/susceptibility status of mosquito populations of public health concern. The objectives here were to determine resistance status for six AIs used in adult mosquito control in the United States to assess how resistance/susceptibility differs between AI, mosquito species (states where > 1 species collected), and between years (some populations sampled for 2 yr). Field-collected eggs from 21 mosquito populations of six different species or hybrid species (Aedes albopictus Skuse [Diptera: Culicidae], Aedes aegypti L. [Diptera: Culicidae], Culex nigripalpus Theobald, Culex pipiens L. [Diptera: Culicidae], Culex quinquefasciatus Say [Diptera: Culicidae], Cx. pipiens/quinquefasciatus) were obtained. Centers for Disease Control and Prevention bottle bioassays were used to assess the resistance/susceptibility status for six AIs (bifenthrin, deltamethrin, etofenprox, malathion, permethrin, and phenothrin). World Health Organization guidelines were used to classify mosquitoes as susceptible (98-100% mortality at diagnostic time [DT]), possibly resistant (80-97% mortality at DT), or resistant (

Groundskeepers spend most of the year working outdoors, exposing them to heat and solar ultraviolet (UV) radiation and increasing their risk to related adverse health effects. Various studies on heat and UV exposures in different occupations have been published, but those on groundskeepers are rare. The purpose of this study was to assess the exposure to heat stress and solar UV radiation among groundskeepers in an eastern North Carolina university setting. Wet bulb globe temperature (WBGT) index using a heat stress monitor and UV effective irradiance (UV

Mosquitoes are a nuisance and potentially transmit pathogens causing numerous diseases worldwide. Homeowners and others may hire private companies to alleviate mosquito-related issues. Here, two pyrethroids (Suspend Polyzone [deltamethrin] and Bifen Insecticide/Termiticide [bifenthrin]) were evaluated on properties in North Carolina for 23 wk from 18 May through 19 October 2015. Properties were treated using backpack mist blowers every 21 d. At 17 fixed sampling locations, Centers for Disease Control and Prevention carbon dioxide-baited traps were deployed overnight once/week for the duration of the experiment. Oviposition traps were deployed weekly at the same locations. Differences were observed in mosquito abundance between neighborhoods, treatments, and weeks and differences varied between species. Mosquito abundance was generally significantly higher in traps placed on control properties (no insecticide) compared to traps placed on treatment properties. Bifenthrin and deltamethrin showed differences from each other in efficacy, but this varied between neighborhoods and species. Future studies could test the efficacy of barrier sprays at different application frequencies and/or in conjunction with weather monitoring. Coupled with regular mosquito surveillance and using integrated pest management principles, barrier sprays can be an effective tool for suppression of mosquito populations.

Chikungunya, dengue, and Zika viruses (CHIKV, family Togaviridae, genus Alphavirus; DENV and ZIKV, family Flaviviridae, genus Flavivirus) are arboviruses that cause human epidemics. Due to the lack of vaccines for many mosquito-borne diseases, there is a need for mosquito control. In the US and other regions, residual barrier insecticide sprays are applied to foliage where female mosquitoes rest and/or sugar feed between blood meals. Residual sprays are an important control method for anthropogenic day-active sylvan mosquitoes such as Aedes albopictus (vector of CHIKV, DENV, and ZIKV) that are difficult to control using ultralow-volume sprays applied only at dusk or dawn when these mosquitoes are not active. In this exploratory study, we analyzed the extent to which ingestion of a sublethal dose of the active ingredient bifenthrin affected vector competence (i.e., infection, dissemination, and transmission) of Ae. albopictus for DENV and ZIKV. Two incubation periods (IPs; 7 and 14 d) were tested at 28°C for insecticide-fed and sugar-fed mosquitoes. We show that mosquitoes that were fed bifenthrin (0.128 µg/mL) mixed with sucrose solution exhibited significantly lower DENV infection rates and body titers after a 14-d IP. During the 7-d IP, one mosquito (sugar group) transmitted ZIKV. During the 14-d IP, 100% of mosquitoes showed body and leg ZIKV infections, and one mosquito (sugar+bifenthrin group) transmitted ZIKV. This is a preliminary communication, and more studies will be required to further investigate these findings. We expect the findings of this small-scale study to spur larger-scale investigations of the impacts of insecticides on mechanisms regulating vector competence, and exposure to other active ingredients, and aid in development of new insecticides.

Background Each year, the average number of nonfatal occupational injuries among landscaping and groundskeeping workers are consistently above the total number of injuries for all other occupational injuries among worker in the U.S. From 2004 to 2007, fatalities among groundskeepers averaged 13.3 per 100,000 workers compared to an overall rate of 4.0 fatalities per 100,000 for all U.S. workers with the majority reported as either Hispanic or Latino. Objective The aims of this project were to describe the use of personal protective equipment and work safety climate among a sample of landscaping and groundskeeping workers employed by public universities in North Carolina (N = 67). Methods Data from a cross-sectional study was collected among workers using group- administered surveys. Statistical associations with work safety climate were tested between personal, work and safety behavior characteristics with work safety climate scores using one-way ANOVA. Results Nearly half of workers (49.3%) reported experiencing one or more work-related injuries or illnesses within the past 12 months. While work safety practices were perceived as being very important to management, only 56.7% reported having regular safety meetings. In bivariate analysis, work safety climate scores were significantly lower among those reporting race "other than white" (P = 0.01). Conclusions This is the first study of its kind to evaluate work safety climate among landscaping and groundskeeping workers. Although self-reported safety practices were moderate, minority workers described their work safety climate as being poor. As a pilot study, these results suggest that employers of landscaping and groundskeeping workers could do more to improve safety climate within the organization with an emphasis on safety training for minority and underrepresented workers.

Agricultural work is a physically demanding occupation. The purpose of this project was to describe the prevalence of work-related musculoskeletal disorders (WMSDs) and self-reported pain among Latino farmworkers who work extensively hand harvesting sweet potatoes. Data were obtained from a cross-sectional survey of farmworkers (N = 120) in eastern North Carolina. Univariate and bivariate analyses were used to describe personal, work characteristics, and self-reported pain associated with musculoskeletal injuries. Overall, 79% of farmworkers reported any type of pain or discomfort. The highest reported areas of pain were in the back (66%) and shoulder areas (31%). Younger participants experienced more shoulder pain (P = .04) than older workers, and working more than 5 years as a farmworker was significantly associated with back pain (P = .01). Interventions aimed at administrative and engineering controls for reducing risk factors that contribute to WMSDs are warranted.

Background Vector-borne diseases are an important cause of morbidity and mortality in the USA. Effective, convenient prevention methods are needed. Long-lasting permethrin-impregnated (LLPI) clothing can prevent tick bites, however, additional information is needed on the real-world effectiveness and safety of this preventative measure. Methods In this pilot study, we recruited state and county park employees from North Carolina to wear LLPI uniforms for three months during the summer of 2016. We collected spot urine samples for biomonitoring of permethrin metabolites at one week, one month and three months after first use of the LLPI uniform. Following three months of wear, we collected pants and socks and analyzed them for permethrin content and mortality to ticks and mosquitoes. Results Thirteen park employees were included in the analysis. Bioactive amounts of permethrin remained in all clothing swatches tested, although there was great variability. Tick mortality was high, with 78% of pant and 88% of sock swatches having mean knockdown percentages ≥ 85%. In contrast, mosquito mortality was low. Over the study period, the absorbed dosage of permethrin averaged < 4 μg/kg/d of body weight based on measurements of three metabolites. Conclusions LLPI clothing retained permethrin and bioactivity against ticks after three months of use in real-world conditions. The estimated absorbed dosage of permethrin was well below the U.S. EPA level of concern, suggesting that LLPI clothing can be used safely by outdoor workers for tick bite prevention. Electronic supplementary material The online version of this article (10.1186/s13071-019-3314-1) contains supplementary material, which is available to authorized users.

Zika virus (ZIKV) is primarily transmitted to humans by Aedes aegypti and Ae. albopictus. Vector&ndash, virus interactions influencing vector competence vary and depend on biological and environmental factors. A mosquito&rsquo, s chronological age may impact its immune response against virus infection. Insecticides, source reduction, and/or public education are currently the best defense against mosquitoes that transmit ZIKV. This study assessed the effects of a mosquito&rsquo, s chronological age at time of infection on its response to ZIKV infection. We exposed young (6&ndash, 7 d post-emergence) and old (11&ndash, 12 d post-emergence) Ae. albopictus to a sublethal dose of bifenthrin prior to oral exposure to blood meals containing ZIKV (7-day incubation period). Old mosquitoes experienced a significantly (p &lt, 0.01) higher rate of mortality than young mosquitoes. Significantly higher ZIKV body titers (p &lt, 0.01) were observed in the old control group compared to the young control group. Significantly higher (p &lt, 0.01) ZIKV dissemination rates and leg titers (p &lt, 0.01) were observed in old bifenthrin-exposed mosquitoes compared to old control mosquitoes or young bifenthrin-exposed or control mosquitoes. Hence, bifenthrin exposure may increase the potential for virus transmission, however, the degree of these impacts varies with mosquito age. Impacts of insecticides should be considered in risk assessments of potential vector populations.

Approximately 870,000 U.S. workers are employed as landscaping and groundskeeping workers who perform various tasks and use a variety of tools that expose them to high noise levels, increasing their risk to noise-induced hearing loss (NIHL). Several studies on noise exposure and NIHL in other job sectors have been published, but those on groundskeepers are very limited. This study aims to characterize the noise exposure of groundskeepers. Participants were monitored over their entire work shift for personal noise exposure by wearing noise dosimeters at shoulder level, 4 in from the ear. Using two different dosimeter settings (OSHA and NIOSH), the time-weighted averages (TWAs) and 1-min averages of noise exposure levels in decibels (dBA) were obtained. The participants were also asked to fill out an activity card daily to document their tasks, tools used, location and noise perception. Sound pressure levels (SPLs) produced by various groundskeeping equipment and tools were measured at full throttle near the ear of the operator using a sound level meter. These measurements were used to assess worker noise exposure profiles, particularly the contributing source of noise. The overall mean OSHA and NIOSH TWA noise exposures were 82.2±9.2 (range of 50.9-100 dBA) and 87.8±6.6 dBA (range of 67.2-102.9 dBA), respectively. Approximately 46% of the OSHA TWAs exceeded the OSHA action limit of 85 dBA. About 76% of the NIOSH TWAs exceeded 85 dBA, and 42% exceeded 90 dBA. The SPLs of equipment and tools measured ranged from 75- 106 dBA, most of which were at above 85 dBA and within the 90-100 dBA range. Hand-held power tools and ride-on equipment without enclosed cab may have contributed significantly to worker noise exposure. This study demonstrates that groundskeepers may be routinely exposed to noise levels above the OSHA and NIOSH exposure limits, and that the implementation of effective hearing conservation programs is necessary to reduce their risk to NIHL.

Mosquitoes are a nuisance and can transmit pathogens to humans and other animals, resulting in notable morbidity and mortality. Organized mosquito control programs conduct surveillance, source reduction, treatment of mosquito oviposition sites, and adulticiding to protect public health. However, in some regions, there has been a decline in county and municipal mosquito control programs, and homeowners increasingly contract with private mosquito control companies or address mosquito-related issues themselves at the household level. The extent to which these services are being used, the potential for mosquito and/or insecticide exposure around the home, and the access to these services by individuals of different socioeconomic categories are not known. We conducted regional (western, central, eastern) assessments of public perception and knowledge of mosquito control services in a variety of communities of different socioeconomic categories (low, moderate, high) and types (urban, suburban, rural) in 3 North Carolina counties. We also assessed the respondents' basic knowledge of mosquito-borne diseases. Most respondents thought mosquito control was important to protect against both nuisance mosquitoes and mosquito-borne disease. The majority of people would pay ≤$50/year for mosquito control and most thought this should be covered by municipal/county taxes. Many respondents (31%, 95% confidence interval [CI] 26-35%) personally undertake mosquito control on their properties, but only 5.3% (95% CI 3.1-7.5%) contract with professional mosquito control services, with no significant differences between region, community type, or socioeconomic category in the proportion using private mosquito control services. While there were significant differences between factor levels (3 regions, 3 community types, 3 socioeconomic categories) in some responses, there were no significant differences observed between respondents, regardless of factor level, in the willingness to contribute funds to a community-based mosquito control program.

Groundskeepers may have increased risk to noise-induced hearing loss due to the performance of excessively noisy tasks. This study assessed the exposure of groundskeepers to noise in multiple universities and determined the association between noise exposure and variables (ie, university, month, tool used). Personal noise exposures were monitored during the work shift using noise dosimetry. A sound level meter was used to measure the maximum sound pressure levels from groundskeeping equipment. The mean Occupational Safety and Health Administration (OSHA) and National Institute for Occupational Safety and Health (NIOSH) time-weighted average (TWA) noise exposures were 83.0 ± 9.6 and 88.0 ± 6.7 dBA, respectively. About 52% of the OSHA TWAs and 77% of the NIOSH TWAs exceeded 85 dBA. Riding mower use was associated with high TWA noise exposures and with having OSHA TWAs exceeding 85 and 90 dBA. The maximum sound pressure levels of equipment and tools measured ranged from 76 to 109 dBA, 82% of which were >85 dBA. These findings support that groundskeepers have excessive noise exposures, which may be effectively reduced through careful scheduling of the use of noisy equipment/tools.

In hot weather, thermal heat generated by the body, combined with environmental heat from the sun, can lead outdoor workers to experience heat-related stress, severe illness, or even death. The aims of this study were to estimate the prevalence of heat-related symptoms and potential risk factors associated with sun safety-related behavior among Latino farmworkers. Data from interviewer-administered questionnaires were collected from a cross-sectional survey among farmworkers (N = 158) from August to September 2013. Data analysis assessed associations between work activities, sun safety behavior, and the prevalence of heat-related illness (HRI) symptoms among workers. Nearly two thirds (72%) of farmworkers experienced at least one HRI symptom and lacked proper cooling methods when working outdoors. Most workers reported wearing long-sleeved shirts (85%), long pants (98%), and baseball caps (93%). The prevalence of having one HRI symptom was 72% and 27% among workers having three or more HRI symptoms. The majority of farmworkers experience symptoms of HRI and are not provided with proper shade protection when working outdoors. Increased emphasis on administrative controls, particularly educating field supervisors and workers on how to avoid and recognize HRI, should be a priority.