Dark Chemistry during Bleach Cleaning Enhances Oxidation of Organics and Secondary Organic Aerosol Production Indoors

Abstract

Bleach can oxidize volatile organic compounds (VOCs) and contribute to secondary organic aerosol (SOA) indoors. During the House Observations of Microbial and Environmental Chemistry (HOMEChem) campaign, we observed indoor terpene mixing ratios decrease during bleach cleaning periods, with simultaneous increases in oxidized VOC (OVOC) products. Cooking just prior to bleach cleaning significantly increased SOA due to uptake of bleach-related OVOCs onto cooking aerosols. While SOA formation occurred, it was small (<3%) relative to total organic aerosol mass concentrations. Bleach cleaning chemistry also produced several potentially toxic chlorinated and nitrogenated VOCs indoors, including isocyanates, cyanogen chloride, and chlorocarbons. Observed volatile chlorinated organic acids were likely impurities from the bleach. The bleach-induced terpene oxidation, SOA formation, and chlorinated/nitrogenated VOC production were independent of indoor illumination, consistent with dark chemical production. These observations add to previous studies that demonstrate bleach as a source of potentially harmful primary and secondary pollutants to indoor air.

Experimental evidence that halogen bonding catalyzes the heterogeneous chlorination of alkenes in submicron liquid droplets

“…The half-life (s 1/2 ) of Sqe (in the absence of additives) is $56 min under indoor conditions when bleach is used ([Cl 2 ] $ 100 ppb). 35,37 However, in a mixture with other skin lipids such as LA (or OA), s 1/2 for Sqe decreases substantially to $3.6 min at the same [Cl 2 ]. This indicates that skin lipid reactivity is a more complex function of the surface and gas phase environment, in which trace constituents and weak interactions play more important roles that previously imagined.…”

“…bleach cleaning ([Cl 2 ] $ 100 ppb). 25,[35][36][37][38][39] This paper is organized as follows. The apparatus and experimental approach for quantifying heterogeneous chlorination rates, reaction products as well as determining effective uptake coefficients are described in Experimental design.…”

Quantification and source characterization of volatile organic compounds from exercising and application of chlorine‐based cleaning products in a university athletic center

“…Hypochlorite bleach is used to disinfect surfaces in homes, offices, pools, and gyms, possibly leading to respiratory ailments for those who work in the cleaning industry 34‐37 . Bleach can also react with ammonia and amides on surfaces, producing chloramines, chlorine gas, nitryl chloride, 38 cyanogen chloride, methyl isocyanate, and ethyl isocyanate 39 some of which are associated with health impacts 34‐37,39,40 …”

Formation of Oxidized Gases and Secondary Organic Aerosol from a Commercial Oxidant-Generating Electronic Air Cleaner

“…Organic chloride formation can be associated with chlorine-containing VOCs which may be emitted or formed through interactions with cleaning products. 81 , 82 …”