Biological Monitoring and Bleeding Edge


Thursday, May 26, 2016, 1:00 PM - 3:20 PM


Exposure to Lead from Industrial Paints and Coatings: Is This Still a Potential Hazard in Workplaces?

D. Radnoff, Alberta Jobs, Skills, Training and Labour, Edmonton, AB, Canada

Situation/Problem: Historically, lead has been used as a pigment in paints and also to improve the qualities of the product. Under the current federal legislation in Canada, a lead paint is considered a product that contains more than 90 mg/kg lead. Employers may not be aware that products with applied industrial coatings can still contain lead. There is no labeling required for such products on which the coating has already been applied. Moreover, there is very little guidance for employers on the potential for an occupational hazard when coatings containing low levels of lead are disturbed.

Resolution: Alberta Jobs, Skills, Training and Labour conducted a literature review and some limited sampling to better quantify the potential for a workplace hazard.

Results: Lead was found in new industrial coatings above the Canadian standard. Employers where these results were found were not aware of the lead content. Studies in the published literature show that workers may still be exposed to lead in excess of occupational standards, even when the lead content is low, but this data is very limited. Further, the relationship between the amount of lead in the coating and how much becomes airborne is not established. Regardless of the lead content in the coating, the lead can still become airborne and contaminate surfaces over time.

Lessons learned: More work is required to improve employer awareness of this potential hazard and to better quantify the potential exposure hazard to workers when disturbing coatings containing low levels of lead.



Legionella in Residential and Commercial Properties: Routine Monitoring and Prevention

J. Birkebak, C. Lively, M. Reed, and E. Sobek, Assured Bio Labs, LLC, Oak Ridge, TN; P. Riccobono, Conditioning and Control Systems, Inc., Englewood, NJ; J. Leitner and M. Borello, Environmental Building Solutions, LLC, New York, NY

Objective: Legionella has received increased media recognition recently due to several large scale lethal outbreaks, including the Pittsburgh Veterans’ Affairs clinic in 2012 and the New York City Bronx outbreak of 2015. Despite the seemingly intermittent diagnosis of Legionellosis, routine monitoring reveals that Legionella is commonly and consistently recovered in cooling towers as well as potable water. The CDC estimates that Legionellosis is greatly under reported, partly due to the current medical techniques for diagnosis. The best way to ensure a healthy environment for tenants and employees and liability free operations for owners is to implement a schedule for routine testing and response actions when Legionella is detected. Here we set out to illustrate the increasing need for a Legionella monitoring program and provide guidelines for testing methodologies and response actions.

Methods: Over four years of results for routine Legionella testing of properties in New York City and other areas are presented. Both culture and qPCR were used in some settings.

Results: Over the past three years we have found that Legionella is frequently recovered from water samples in residential and commercial properties in New York City. Over half of projects were found to contain Legionella. Despite the recently expanded testing of cooling towers, the bacterium was more commonly found in potable hot water systems than in cooling towers. Some buildings consistently test positive for Legionella while others implement treatment protocols in order to control Legionella contamination. Even though Legionella is found, often no illness or outbreak is reported. This may be primarily due to the current medical methods that only screen for one serogroup of one species. Research has shown that many people do produce antibodies indicative of past Legionellosis. There are two main options for Legionella testing currently available: the traditional culture method and quantitative polymerase chain reaction (qPCR). Each option has benefits and drawbacks and which to use may seem unclear. While the culture method remains the “gold standard” for detection for environmental Legionella detection, it requires a long turnaround time which may not be feasible while combating or tracking an ongoing outbreak or immediately following response actions to ensure proper decontamination. QPCR, while it can be run with same day turnaround for immediate results, cannot distinguish between living and nonliving Legionellae and inter-lab comparison of results can be difficult given that there is no established and universally accepted methodology. Guidelines on which method will best fit a given circumstance will be presented.

Conclusions: The increased media attention will likely lead to an increase in monitoring requirements, social attention, and raise the legal stakes for owners and managers of cooling towers and potable water systems. With the increasing social and medical relevance of Legionella infection and the prevalence of Legionella recovered from cooling towers and potable water systems, a routine monitoring program is strongly advisable.



Passive ​Wristband Sampler Technology Used to Build Bridges: Pilot Study Examples

K. Anderson, Oregon State University, Corvallis, OR

Objective: Accurately assessing the breadth of a person’s exposures to environmental toxicants is central to the challenge of studying environmental health effects. The lack of low cost, easy to use personal sampling technology hinders many situations where sampling is challenging.

Methods: Personal sampling wristband technology (BRIDGES: Biological Response Indicator Devices for Gauging Environmental Stressors) was developed specifically because Public Health researchers and Community partners were enthusiastic about its broad potential to fill a key gap in Public Health. The wristbands can provide a foundation to measure organic chemicals that are a crucial component of the exposome. Volatile and semi-volatile organic chemicals (chemical with a boiling point less than 450°C) can be quantified from the wristband.

Results: The wristband can be screened, in a single method, for over 1,400 organic compounds. We can quantify several 100 analytes such as PAHs, pesticides, flame retardants, PCBs, and many consumer products. The extracts can be used to assess the bioactivity of the actual exposure mixture of the individual wearing the wristband. Several pilot studies have been completed. Polycyclic aromatic hydrocarbons (PAHs) were detected and quantified, and two oxygenated PAHs were quantified on journeymen who wore the wristband while roofing and pre-apprentices at a training center. all participants. Thirty-one PAHs were detected, including large PAHs such as benzo[e]pyrene (mp 178°C, bp 493°C) and total PAHs ranged from 230 to 4,600 ng/wristband. In another study, young children’s exposure to flame retardants was investigated. Wristband recoveries averaged 98%, 103% for brominated diphenyl ethers, and phosphate ester flame retardants, respectively. The between day precision of spiked wristbands was < 9%. Some children’s wristbands had 20 quantifiable flame retardants. In a western Africa study, we found that wristbands contained 2 to 10 pesticides, with deltamethrin and cypermethrin most frequently detected in 99 and 94% respectively.

Conclusions: We have found that people are actually eager to wear the wristband and we have 85-100% compliance in studies to date. Our passive sampling technology can be deployed in hours to disaster areas in a way that synergizes with NIEHS’s programs to develop effective analyses of the human health impacts of disasters. Individuals and communities can be empowered with this chemical exposure information which helps build community resilience.



Piloting Development of a Wearable, Real-Time Heat Strain Monitor

R. Reed, University of Arizona, Tucson, AZ

Objective: The objective of this study is to develop a real-time, wearable heat strain monitor that can predict core body temperature and potential heat related incidents. Because of the barriers associated with monitoring heat strain, its individualized nature, and the lack of regulatory limits, few employers regularly perform personal heat strain monitoring. The ACGIH® Threshold Limit Value (TLV®) for heat stress utilizes a method that combines metabolic and environmental heat sources to determine one’s risk of excessive heat strain. This work attempts to assess these heat sources in real-time using sensor technologies and predict core body temperature (CBT).

Methods: Physiologic (heart rate, activity, skin temperature) and environmental (dry bulb temperature, relative humidity) measures were collected for approximately five subjects using real-time, wearable sensors. CBT were measured using the CorTemp® ingestible temperature sensor (HQ Inc., Palmetto, FL). A type of machine learning technique called artificial neural networks (ANN) is being utilized to develop models capable of predicting core body temperature using sensor inputs. If ANN proves ineffective, prediction will be attempted using vector auto-regressive time series methods. MATLAB (MathWorks, Natick, MA) will be used for data cleaning, filtering, smoothing, and analysis.

Results: The average HR is 157 bpm, the average calorie expenditure is 14.4 calories per minute, while the average steps per minute is 170. Preliminary CBT data require​​​d substantial cleaning and smoothing, while HR and other sensor data are comparatively noise free. After initial model training, we anticipate excluding 1-2 inputs because they do not contribute to CBT prediction. We hope to successfully predict CBT in real-time for working individuals with a wearable monitor. Potential limitations include a lack of inputs for hydration status, perspiration, precipitation, and convective and radiant heat sources. In addition, the small sample size does not allow for machine learning across a variety of body types, races, ethnicities, or other modifiers such as personal protective equipment.

Conclusions: We aim to reduce the barriers associated with heat strain monitoring in the workplace and at sporting events. We believe a wearable, real-time heat strain monitor with alerting system can accomplish this, and this project lays the groundwork for such a device.



Analysis of Los Angeles Taxi Drivers’ Urinary PAH Metabolites and Their Associations with Occupational Exposure to Traffic Pollutants

N. Yu, University of California Los Angeles, Los Angeles, CA

Objective: Polycyclic aromatic hydrocarbons (PAHs) is one of the major hazardous traffic emission constituents. Many PAH species have been identified as carcinogens, mutagens, and teratogens, and their metabolites can cause damage to human DNA. About 4,000 taxi drivers are working in Los Angeles area with potentially high occupational particulate matter and PAH exposures, however, there is a data and knowledge gap on quantifying their PAH exposure levels and the associated health impacts.

Methods: In this study, 22 never smoked Los Angeles taxi drivers were recruited and monitored for 4 consecutive work days, a 6-hour work shift/day, for their ultrafine particles and PM2.5 exposures. In the last two monitored days, each driver’s taxi will be installed with a high efficiency particulate cabin air filter for exposure intervention. The taxi driver urine samples were also collected both just before (pre shift) and right after (post shift) their daily work shift. Nine different urinary monohydroxylated PAH metabolites were analyzed, which included 1- and 2-hydroxynaphthol (1- and 2-NAP), 1-, 2-, 3- hydroxyphenanthrene (1-, 2- and 3-PHE), 2-, 3-, 9-hydroxyfluorene (2-, 3-, and 9-FLU), and 1-hydroxypyrene (1-PYR). Urinary malondialdehyde (MDA) was also analyzed and used in this study as an oxidative stress marker. Four UCLA never smoked researchers served as a control group. Their urine samples were also collected and analyzed following the same procedure that was administered to the taxi driver group.

Results: Paired t tests were conducted to compare pre and post work shift samples from the taxi drivers, and the results showed no significant differences (p<0.05) between pre and post work shift urinary PAH metabolites and MDA levels. Taxi driver urinary MDA didn’t show significant correlations with any analyzed urinary PAH metabolites. Comparing urinary MDA and monohydroxylated PAH metabolite levels, within the total of nine analyzed metabolites, four of the metabolite mean levels in the driver group were higher than the control group significantly with group t tests (p<0.05). These four metabolites were 1- and 2-NAP, 1-PYR and 9-FLU. No differences were detected for urinary MDA levels between the taxi driver and control groups.

Conclusions: A mixed effect longitudinal model results showed the taxi driver 1-PYR levels were significantly affected by their work time ultrafine particle and PM2.5 exposure levels.



Application of a Systems Approach to Link Safety and Productivity to Power Hand Tool Evaluation and Procurement

M. Geiger, Naval Safety Center, Fairfax, VA; D. Wasserman, Consulting Engineer, Frederick, MD

Situation/Problem: Powered hand tools have become essential in the industrial environment since their introduction in the late 1870s. Risks linked to this technology include noise, segmental vibration, and a range of ergonomic/repetitive motion risks. While exposures and potential health outcomes are commonly correlated with well described dose response relationships, regulatory controls are not consistently imposed on procurement and support activities. This is a major issue in the US, where OSHA regulatory standards lag significantly behind current scientific knowledge. Standards for hand-arm vibration are advisory rather than mandatory. Procurement often considers initial purchase costs as the primary factor in product selection. The result has been use of tools and work practices inconsistent with best available technology and related persistence of poorly controlled occupational exposures.

Resolution: A team of health and safety professionals from the US Department of Defense (DOD) and NIOSH and procurement/logistics experts from the General Services Administration and DOD was formed in 2008. This group developed procurement guidelines considering vibration and other safety and health factors. Collaboration with industry and SAE International led to development of a process standard. Aerospace Standard AS 6228, for power tool evaluation and procurement considers life-cycle costs, productivity, noise, vibration and other ergonomic considerations in a semi-quantitative rating scale.

Results: The US Government’s commodity manager for powered hand tools has adapted this standard in evaluation and product selection. Approximately 130 new tools have been introduced into the supply system. Outreach is being made within DOD and to allied industries.

Lessons learned: A standardization approach may be considered where process improvements and selection of best available technology benefit productivity, cost and safety. A multidisciplinary team and persistent outreach, was needed to reach the various customers and product managers. This methodology focused upon power tools, but could also be applied to help overcome the absence of strong safety and health regulatory criteria for other commodities and processes.



Estimating the Dermal Exposure of Synthetic Musks from Personal Care Products by Using Vertical Diffusion Cell

Y. Hsu, W. Tseng, and S. Tsai, National Taiwan University, Taipei, Taiwan

Objective: Emerging environmental pollutants have caused concerns in recent years. For example, a variety of chemical components such as synthetic musks (e.g., galaxolide (HHCB) and tonalide (AHTN)),  from personal care products (PCPs), may cause exposures through skin contact. To assess the possible health effects, the dermal exposures of synthetic musks were estimated in this research.

Methods: The vertical diffusion cell (VDC), an in vitro method, was used to simulate skin exposures in this study. Porcine skin was selected as the substituted skin for human exposure, while phosphate buffered saline (PBS) solution was used as the receptor media. The flow rate of the VDC system was about 10.13 ml/hr., and the temperature was set at 37 degrees Celsius. Samples from the VDC system were taken periodically to determine the permeation profiles. The 65μm PDMS/DVB solid-phase microextraction (SPME) fiber was exposed to the headspace over the samples. After adsorption equilibrium has been reached, the SPME fiber was inserted into the injector of the gas chromatography with tandem mass spectrometry (GC/MS/MS) for thermal desorption and further analysis.

Results: The SPME procedure coupled with GC/MS/MS analysis for the determinations of synthetic musk in PBS solution was established in this study. No carry over effect was observed from the thermal desorption of the sample. The detection range for nitro and polycyclic musk were 0.1 ng/ml-20 ng/ml and 0.01 ng/ml -2 ng/ml, respectively. The skin permeation profiles of synthetic musks from different PCPs were estimated. Health risks associated with the possible exposures were also assessed.

Conclusions: VDC system was applied in this study to estimate the skin exposures of synthetic musks from PCPs. With SPME procedure, advantages over conventional methods, such as solvent-free and time-saving, were reached. The sensitivities of the method for different musk compounds were low enough to determine the concentrations after skin permeation.​