Previous research has shown that desktop 3D printers can emit large numbers of ultrafine particles (UFPs, particles less than 100 nm) and some hazardous volatile organic compounds (VOCs) during printing, although very few filament and 3D printer combinations have been tested to date. Here we quantify emissions of UFPs and speciated VOCs from five commercially available filament extrusion desktop 3D printers utilizing up to nine different filaments by controlled experiments in a test chamber. Median estimates of time-varying UFP emission rates ranged from ∼10(8) to ∼10(11) min(-1) across all tested combinations, varying primarily by filament material and, to a lesser extent, bed temperature. The individual VOCs emitted in the largest quantities included caprolactam from nylon-based and imitation wood and brick filaments (ranging from ∼2 to ∼180 μg/min), styrene from acrylonitrile butadiene styrene (ABS) and high-impact polystyrene (HIPS) filaments (ranging from ∼10 to ∼110 μg/min), and lactide from polylactic acid (PLA) filaments (ranging from ∼4 to ∼5 μg/min). Results from a screening analysis of potential exposure to these products in a typical small office environment suggest caution should be used when operating many of the printer and filament combinations in poorly ventilated spaces or without the aid of combined gas and particle filtration systems.

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Infants spend most of their time sleeping, where they are in intimate contact with their crib mattresses. In this study, we analyzed the cover and foam layers of 20 new and used crib mattresses for selected chemical additives. Seventeen of the 20 crib mattress covers contained at least one identifiable plasticizer, with concentrations ranging from 1 to >35% by weight. Sixty percent of the covers contained a total plasticizer content of >9% by weight. Nine of the 20 covers contained either bis­(2-ethylhexyl) phthalate (DEHP) or diisononyl phthalate (DINP). In contrast, phthalate alternatives, including diisononyl 1,2-cyclohexanedicarboxylic acid (DINCH) and bis­(2-ethylhexyl) isophthalate (iso-DEHP), were the most frequently identified plasticizers in crib mattresses manufactured after the U.S. Consumer Product Safety Improvement Act (CPSIA) went into effect. Flame retardants, including pentabromodiphenyl ether (pentaBDE) congeners and triphenyl phosphate (TPP), and unreacted isocyanates (NCO) were also identified in crib mattresses with polyurethane foam.

Retail buildings have a potential for both short-term (customer) and long-term (occupational) exposure to indoor pollutants. However, little is known about volatile organic compound (VOC) concentrations in the retail sector and influencing factors, such as ventilation, in-store activities, and store type. We measured VOC concentrations and ventilation rates in 14 retail stores in Texas and Pennsylvania. With the exception of formaldehyde and acetaldehyde, VOCs were present in retail stores at concentrations well below health guidelines. Indoor formaldehyde concentrations ranged from 4.6 ppb to 67 ppb. The two mid-sized grocery stores in the sample had the highest levels of ethanol and acetaldehyde, with concentrations up to 2.6 ppm and 92 ppb, respectively, possibly due to the preparation of dough and baking activities. Indoor-to-outdoor concentration ratios indicated that indoor sources were the main contributors to indoor VOC concentrations for the majority of compounds. There was no strong correlation between ventilation and VOC concentrations across all stores. However, increasing the air exchange rates at two stores led to lower indoor VOC concentrations, suggesting that ventilation can be used to reduce concentrations for some specific stores.