Exposure of Highway Maintenance Workers to Fine Particulate Matter and Noise

Abstract

in this study, we assessed the mixed exposure of highway maintenance workers to airborne particles, noise, and gaseous co-pollutants. the aim was to provide a better understanding of the workers' exposure to facilitate the evaluation of short-term effects on cardiovascular health endpoints. to quantify the workers' exposure, we monitored 18 subjects during 50 nonconsecutive work shifts. Exposure assessment was based on personal and work site measurements and included fine particulate matter (PM 2.5 ), particle number concentration (PNC), noise (leq), and the gaseous co-pollutants: carbon monoxide, nitrogen dioxide, and ozone. Mean work shift PM 2.5 concentrations (gravimetric measurements) ranged from 20.3 to 321 μg m −3 (mean 62 μg m −3 ) and PNC were between 1.6 × 10 4 and 4.1 × 10 5 particles cm −3 (8.9 × 10 4 particles cm −3 ). Noise levels were generally high with leq over work shifts from 73.3 to 96.0 dB(a); the averaged leq over all work shifts was 87.2 dB(a). the highest exposure to fine and ultrafine particles was measured during grass mowing and lumbering when motorized brush cutters and chain saws were used. Highest noise levels, caused by pneumatic hammers, were measured during paving and guardrail repair. We found moderate spearman correlations between PNC and PM 2.5 (r = 0.56); PNC, PM 2.5 , and Co (r = 0.60 and r = 0.50) as well as PNC and noise (r = 0.50). Variability and correlation of parameters were influenced by work activities that included equipment causing combined air pollutant and noise emissions (e.g. brush cutters and chain saws). We conclude that highway maintenance workers are frequently exposed to elevated airborne particle and noise levels compared with the average population. this elevated exposure is a consequence of the permanent proximity to highway traffic with additional peak exposures caused by emissions of the work-related equipment.

Associations of Short-Term Particle and Noise Exposures with Markers of Cardiovascular and Respiratory Health among Highway Maintenance Workers

“…LDSA, a measure of exposure to UFP, was highly correlated to the UFP particle number concentration (PNC) (Pearson correlation r = 0.96). A more detailed description of exposure to air pollutants and noise during highway maintenance work has been described previously (Meier et al 2013a). The slight differences between the means reported in Table 1 and the means reported in our previous publication are attributable to excluded observations because of missing or invalid health data.…”

“…The exposure assessment was presented in detail elsewhere (Meier et al 2013a). Briefly, personal real-time PM 2.5 measurements (PM 2.5Realtime ; 1-min resolution) were made using a personal DataRam pDR1000 real-time particulate monitor (Thermo Scientific, Waltham, MA, USA) attached on the subject’s back.…”

“…A detailed description about handling of missing real-time exposure data has been provided previously (Meier et al 2013a). Briefly, missing real-time particle data were replaced by estimates based on correlated particle measurements extrapolated to the distribution of the missing pollutant for the same subject, activity, and type of work site: For PM 2.5Realtime , 0.5% missing, estimates based on parallel PM 2.5Realtime measurement, and, if not available, on UFP particle number concentration (PNC).…”

“…We recently described how highway maintenance workers are frequently exposed to air pollutants and noise originating from road traffic and work equipment (Meier et al 2013a). Their mixed exposure to particles and noise may contribute to an increased susceptibility to the development or exacerbation of heart and vascular diseases.…”

Exposure to Fine Particulate Matter Leads to Rapid Heart Rate Variability Changes

“…Fine particulate matter (PM) on roads originates to an important part from traffic and combustion engines which release particles and precursors of secondary aerosols into the air (Riediker et al, 2003;Putaud et al, 2010;Meier et al, 2013). High concentrations occur in particular along busy roads such as highways, which are depending on factors such as traffic counts but also weather and wind (Imhof et al, 2005;Zwack et al, 2011).…”