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Polycyclic aromatic hydrocarbons (PAHs) were analyzed in 70 soils distributed in mountain areas such as Montseny (300-1,700 m), Pyrenees (1,500-2,900 m), Alps (1,100-2,500 m), and Tatras (1,400-1,960 m). Average total PAH concentrations, excluding retene and perylene, were about 400 ng/g in the Pyrenees and 1,300-1,600 ng/g in the other mountain ranges. No correlations between PAH concentrations and total organic carbon were observed. Retene was the major PAH in the Pyrenean soils of lower altitude. No altitudinal dependence was found between soil PAH concentrations and elevation for the whole dataset. However, in the Tatra soils a statistically significant correlation with altitude was observed involving higher concentrations at higher altitude. This correlation was due to the statistically significant altitudinal dependence of the more volatile PAHs. Another observed altitudinal trend concerned the benz[ a]anthracene/(benz[ a]anthracene + chrysene + triphenylene) and the benzo[ a]pyrene/(benzo[ a]pyrene + benzo[ e]pyrene) ratios that exhibited a decrease in the more chemically labile compounds, benz[ a]anthracene and benzo[ a]pyrene, respectively, in the soils located at higher altitude. This observation is consistent with the expected higher photooxidation at higher mountain altitude. [ABSTRACT FROM AUTHOR]

Hexachlorocyclohexanes (HCHs; α‐ and γ‐isomers), endosulfans (α‐ and β‐isomers and the sulfate residue), hexachlorobenzene (HCB), dichlorodiphenyltrichloroethane (DDTs), and polychlorobiphenyls (PCBs) were measured in waters from three European remote mountain lakes situated in the Alps, Pyrenees, and Caledonian mountains. Sampling encompassed both ice‐free and ice‐covered periods at different water column depths. High HCH concentrations were found in all lakes, those in the Alps and Pyrenees (990–2900 pg/L) being among the highest recorded in continental waters. Endosulfans and endosulfan sulfate (120–1150 pg/L) were the second major group of organochlorine contaminants, showing a remarkable stability upon atmospheric long‐range transport. The concentrations of HCB, DDTs, and PCB (4–8, 0.6–16, and 26–110 pg/L, respectively) were low in comparison with other continental waters. Hexachlorocyclohexanes, endosulfans, and HCB were essentially found in the dissolved phase. Phase partitioning of the more hydrophobic compounds exhibited a dependence on temperature and water‐suspended particles. Comparison between different sampling seasons and water depths indicated a remarkable concentration uniformity within lake, but major interlake differences. Normalization to turnover rates showed higher interlake similarity. Preferential accumulation of the less volatile compounds in the Alp lake and significant increase of baseline contributions of organochlorine compounds and residues in the Caledonian lake are also evidenced from these turnover rates. [ABSTRACT FROM AUTHOR]

The air concentrations of organophosphate esters (OPEs) were studied in a network of six remote high-mountain areas of the Pyrenees located along an altitudinal profile between 1619 m and 2453 m above sea level on a restricted planar surface to assess their vertical distribution based on long-range atmospheric transport and temperature gradients. Polyurethane foam passive samplers were used in five periods spanning over three years (September 2017–October 2020). The sum of concentrations of five OPEs were between 5.3 and 100 pg m−3, averaging 16–53 pg m−3 across campaigns at the different locations. These concentrations were much lower than those observed in areas under anthropogenic influence but also than those found in low altitude remote continental sites. A significant progressive change in predominant compounds was observed along the altitudinal gradient, with prevalence of tris(1-chloro-2-propyl) phosphate (TCIPP) or tris(2-chloroethyl) phosphate (TCEP) below or above 2300 m above sea level, respectively. This trend was consistent with the higher volatility of TCEP, which was retained at greater extent at lower environmental temperatures (higher altitude). A significant temperature dependence of the gas phase concentrations was observed for TCEP, TCIPP and triphenyl phosphate (TPHP), which could be explained by retention in the cold periods, predominantly adsorbed in snow, and their release to the atmosphere during snowmelt. This mechanism was consistent with the good agreement found between the vaporization enthalpies measured under laboratory conditions and the experimental values obtained from the slopes of the significant linear regressions when representing the vertical gradients. [Display omitted] • Organophosphate esters (OPEs) in air of continental regions are lowest in mountains. • Air tris(1-chloro-2-propyl) phosphate, the most used, predominates at low altitudes. • Tris(2-chloroethyl) phosphate in air predominates at altitudes above 2300 m • The air levels of abundant OPEs are correlated with the reciprocal of temperature. • OPEs are adsorbed on mountain snow and released into the atmosphere during snowmelt. [ABSTRACT FROM AUTHOR]