Gas chromatographic system for the identification of halogenated pesticides by retention indices using n-alkanes as standards

Volatile Organic Compound (VOC) Contamination in Hotel Rooms: A Pilot Study to Understand Sources and Health Risks

The COVID-19 pandemic drove the use of cleaning products, causing organic solvent contamination in hospitality environments. This pilot study investigated the presence and concentrations of volatile organic compounds (VOCs) in selected hotels in four different US cities with varying star ratings at the end of the pandemic period. Targeting 139 VOCs, 57 were detected across eight groups: alcohols, halocarbons, aromatics, alkanes, terpenes, carbonyls, ethers, and esters, in the indoor air. Alcohols were the most prevalent, especially in lower-rated hotels, suggesting higher use of cleaning supplies. Elevated levels of aromatics were detected in hotels rated under three stars, with a notable disparity compared to higher-rated hotels. Additionally, alkanes and terpenes such as n-tetradecane and d-limonene were consistently detected. Health risk assessment showed concentrations of all VOCs remained below their health criteria for customers. The cumulative cancer risk was 2.25 × 10-6 for hotel workers from chronic occupational exposure to eight carcinogenic VOCs, representing 1/3 of the lifetime risk from these chemicals in the ambient air. Cancer risks from individual VOCs ranged from 0.001 × 10-6 to 1.07 × 10-6, with chloroform accounting for nearly half of the cumulative risk. The findings underscore the need for careful selection and use of furnishings and cleaning supplies and for effective indoor air pollution control and management in hotel indoor environments.

Hydrogen bond basicity of the chlorogroup; hexachlorocyclohexanes as strong hydrogen bond bases

A simple chloroalkane or chlorocycloalkane has a very small hydrogen bond basicity, B = 0.1 units. Since B is often an additive function, it is possible that polychloro-alkanes or -cycloalkanes could have quite large hydrogen bond basicities. Literature data on the 1,2,3,4,5,6-hexachlorocyclohexanes (HCHs) have been analyzed by Abraham's linear free energy relationships to obtain solvation descriptors. These are not extraordinary except for the hydrogen bond basicity, B, which is indeed very large. Values of B for the HCHs are larger than many functionally substituted aliphatic compounds and as large as that of aliphatic amines. We find that B is 0.62-0.72 for the HCHs compared to 0.45 for propanone and 0.70 for ethylamine, the first time that such large hydrogen bond basicities have been identified in compounds with no functional groups. Hydrogen bond basicities are analyzed in order to examine what types of polychlorocompounds give rise to these elevated B values.

Analysis of toxic wastes in tissues from aquatic species. Applications of matrix solid-phase dispersion

One of the difficult tasks in studying toxic wastes in the environment is the process involved in their extraction from biological matrices. This review addresses the regulatory aspects which mandate subsequent analyses in aquatic species and the studies which have addressed these problems from a variety of analytical perspectives. In this regard, the tissue extraction process known as matrix solid-phase dispersion is also reviewed and data are presented indicating that it may provide a generic process for the extraction and subsequent analysis of pesticides, polynuclear aromatic hydrocarbons and polychlorinated biphenyls.