Nonylphenol polyethoxylates (NPEOs) have been widely used as surfactants in many industrial and household applications. However, NPEOs biodegradation in water leads to the formation of estrogenic nonylphenols (NPs). To date, NPs have only been reported in aquatic environments. In this paper, the occurrence of NPs in coastal and urban atmospheres is reported for the first time. Water-to-air volatilization of NPs from estuarine waters is a source of NPs to the estuarine atmosphere. Furthermore, the high concentrations found in the coastal atmosphere of the New York−New Jersey Bight (2.2−70 ng m-3) suggests that the NPs occurrence in the atmosphere may be an important human and ecosystem health issue in urban, industrial, and coastal-impacted areas receiving treated sewage effluents.

Multiphase ozonolysis of aqueous organics presents a potential pathway for the formation of aqueous secondary organic aerosol (aqSOA). We investigated the multiphase ozonolysis of α-terpineol, an oxygenated derivative of limonene, and found that the reaction products and kinetics differ from the gas-phase ozonolysis of α-terpineol. One- and two-dimensional NMR spectroscopies along with GC-MS identified the aqueous ozonolysis reaction products as trans- and cis-lactols [4-(5-hydroxy-2,2-dimethyltetrahydrofuran-3-yl)butan-2-one] and a lactone [4-hydroxy-4-methyl-3-(3-oxobutyl)-valeric acid gamma-lactone], which accounted for 46%, 27%, and 20% of the observed products, respectively. Hydrogen peroxide was also formed in 10% yield consistent with a mechanism involving decomposition of hydroxyl hydroperoxide intermediates followed by hemiacetal ring closure. Multiphase reaction kinetics at gaseous ozone concentrations of 131, 480, and 965 parts-per-billion were analyzed using a resistance model of net ozone uptake and found the second-order rate coefficient for the aqueous reaction of α-terpineol + O to be 9.9(±3.3) × 10 M s. Multiphase ozonolysis will therefore be competitive with multiphase oxidation by hydroxyl radicals (OH) and ozonolysis of gaseous α-terpineol. We also measured product yields for the heterogeneous ozonolysis of α-terpineol adsorbed on glass, NaCl, and kaolinite, and identified the same three major products but with an increasing lactone yield of 33, 49, and 55% on these substrates, respectively.

The atmospheric occurrence of nonylphenols and tertoctylphenol has been assessed at three sites in the lower Hudson River Estuary (LHRE). The samples (n ) 186) were taken from June to December of 1998. Gas-phase nonylphenol (NP) concentrations at a coastal site (Sandy Hook) ranged from below the detection limit (DL) to 56.3 ng m -3 , while concentrations at a suburban site (New Brunswick) ranged from 0.13 to 81 ng m -3 . Gas-phase concentrations of tert-octylphenol (tOP) ranged from

Biogenic volatile organic compounds (BVOCs), including the monoterpene limonene, are a major source of secondary organic aerosol (SOA). While gas-phase oxidation initiates the dominant pathway for BVOC conversion to SOA, recent studies have demonstrated that biogenic hydrocarbons can also directly react with acidic droplets. To investigate whether mineral dust may facilitate similar reactive uptake of biogenic hydrocarbons, we studied the heterogeneous reaction of limonene with mineral substrates using condensed-phase infrared spectroscopy and identified the formation of irreversibly adsorbed organic products. For kaolinite, Arizona Test Dust, and silica at 30% relative humidity, GC-MS identified limonene-1,2-diol as the dominant product with total organic surface concentrations on the order of (3-5) × 10 molecules m. Experiments with O-labeled water support a mechanism initiated by oxidation of limonene by surface redox sites forming limonene oxide followed by water addition to the epoxide to form limonenediol. Limonene uptake on α-alumina, γ-alumina, and montmorillonite formed additional products in high yield, including carveol, carvone, limonene oxide, and α-terpineol. To model tropospheric processing of mineral aerosol, we also exposed each mineral substrate to gaseous nitric acid prior to limonene uptake and identified similar surface adsorbed products that were formed at rates 2 to 5 times faster than without nitrate coatings. The initial rate of reaction was linearly dependent on gaseous limonene concentration between 5 × 10 and 5 × 10 molecules cm (0.22-20.5 ppm) consistent with an Eley-Rideal-type mechanism in which gaseous limonene reacts directly with reactive surface sites. Increasing relative humidity decreased the amount of surface adsorbed products indicating competitive adsorption of surface adsorbed water. Using a laminar flow tube reactor we measured the uptake coefficient for limonene on kaolinite at 25% RH to range from γ = 5.1 × 10 to 9.7 × 10. After adjusting for reactive surface areas, we estimate uptake coefficients for limonene on HNO-processed mineral aerosol on the order of (1-6) × 10. Although this heterogeneous reaction will not impact the atmospheric lifetime of gaseous limonene, it does provide a new pathway for mineral aerosol to acquire secondary organic matter from biogenic hydrocarbons, which in turn will alter the physical properties of mineral dust.

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