Airborne Nanoparticle Concentrations in the Manufacturing of Polytetrafluoroethylene (PTFE) Apparel

Abstract

One form of waterproof, breathable apparel is manufactured from polytetrafluoroethylene (PTFE) membrane laminated fabric, using a specific process to seal seams that have been sewn with traditional techniques. The sealing process involves applying waterproof tape to the seam by feeding the seam through two rollers while applying hot air (600°C). This study addressed the potential for exposure to particulate matter from this sealing process, by characterizing airborne particles in a facility that produces over 1,000 lightweight PTFE rain jackets per day. Aerosol concentrations throughout the facility were mapped, breathing zone concentrations were measured, and hoods used to ventilate the seam sealing operation were evaluated. The geometric mean (GM) particle number concentrations were substantially greater in the sewing and sealing areas (67,000 and 188,000 particles cm −3 ) compared to that measured in the office area (12,100 particles cm −3 ). Respirable mass concentrations were negligible throughout the facility (GM=0.002 mg m −3 in the sewing and sealing areas). The particles exiting the final discharge of the facility's ventilation system were dominated by nanoparticles (number median diameter = 25 nm; geometric standard deviation of 1.39). The breathing zone particle number concentrations of the workers who sealed the sewn seams were highly variable and significantly greater when sealing seams than when conducting other tasks (p<0.0001). The sealing workers' breathing zone concentrations ranged from 147,000 particles cm −3 to 798,000 particles cm −3 , and their seam responsibility significantly influenced their breathing zone concentrations (p=0.03). The finding that particle number concentrations were approximately equal outside the hood and inside the local exhaust duct indicated poor effectiveness of the canopy hoods used to ventilate sealing operations.

Mapping Occupational Hazards with a Multi-sensor Network in a Heavy-Vehicle Manufacturing Facility

“…However, although the number of sensor networks deployed in the ambient environment is growing quickly, they are rare in occupational environments and represent an opportunity to increase the characterization of hazards at low cost. While aerosol mapping in particular has been successful in a variety of occupational and ambient settings (O'Brien, 2003;Peters et al, 2006Peters et al, , 2012Heitbrink et al, 2007;Evans et al, 2008;Ott et al, 2008;Liu and Hammond, 2010;Park et al, 2010;Vosburgh et al, 2011), there is great potential for mapping other hazards such as noise, vibration, radiation, gasses, and vapours (Koehler and Volckens, 2011).…”

Estimating personal exposures from a multi-hazard sensor network

“…[8][9][10][11][12] Advances in open software toolkits and microprocessor platforms have facilitated the development of customized wireless sensor networks, and there is a growing number of examples in the literature. [13][14][15][16][17][18][19][20][21][22] Data from sensor networks may be used to create hazard maps, [23][24][25][26][27][28][29][30][31] which visually communicate risk, 32 identify hazard sources, 24,27 characterize the distribution of hazards in a facility or the environment, 26,27,31 and inform hazard control strategies. 24 We have previously developed a multi-hazard sensor network constructed with low-cost sensors for PM, CO, oxidizing gases (O 3 + NO 2 ) and noise.…”

Mechanisms of carbon nanotube-induced toxicity: Focus on oxidative stress

“…There is evidence that ENMs, including CNTs, may be released in the work environment: many activities have been investigated such as workplace cleaning, packaging/bag filling, reactor cleanout, mixing, cutting composite, and in almost all cases evidence for some release of ENMs in the workplace has been detected (Bello et al, 2009; Han et al, 2008; Kuhlbusch and Fissan, 2006; Maynard et al, 2004; Peters et al, 2009; Tsai et al, 2009; Vosburgh et al, 2011). Some reports describing serious adverse effects of occupational exposure to ENMs have been published: These include several cases of rescue workers present at the World Trade Center in New York City after the tragic events of 9/11 (Aldrich et al, 2010; Gupta, 2011; NIOSH, 2011; Romano, 2011; Zeig-Owens et al, 2011), reports of occupational exposures to mixtures containing nanoparticles in factories in China and India (Jaakkola et al, 2011; Song et al, 2009), a case-report regarding a worker who inhaled an estimated gram of nickel nanoparticles over an approximate 90-minute period, and who died from adult respiratory distress syndrome (Phillips et al, 2010), the development of unusual pulmonary disease in workers exposed to silica nanoparticles (Song et al, 2011), and the development of toxic epidermal necrolysis-like dermatitis in a chemist exposed to high levels of intermediate or final products of dendrimers while performing dendrimer synthesis (Toyama et al, 2009).…”