Geology topics

Lynn M. Crosby

Publications and source records attributed to Lynn M. Crosby.

6 recordsLinked to original sources

USGS2021

Evaluation of Indoor PM2.5 concentrations in a Native American community: A pilot study

Background Indoor air pollution is associated with adverse health effects; however, few studies exist studying indoor air pollution on the Navajo Nation in the southwest U.S., a community with high rates of respiratory disease. Methods Indoor PM 2.5 concentration was evaluated in 26 homes on the Navajo Nation using real-time PM 2.5 monitors. Household risk factors and daily activities were evaluated with three metrics of indoor PM 2.5 : time-weighted average (TWA), 90th percentile of concentration, and daily minutes exceeding 100 μg/m 3 . A questionnaire and recall sheet were used to record baseline household characteristics and daily activities. Results The median TWA, 90th percentile, and daily minutes exceeding 100 μg/m 3 were 7.9 μg/m 3 , 14.0 μg/m 3 , and 17 min, respectively. TWAs tended to be higher in autumn and in houses that used fuel the previous day. Other characteristics associated with elevated PM exposure in all metrics included overcrowded houses, nonmobile houses, and houses with current smokers, pets, and longer cooking time. Conclusions Some residents of the Navajo Nation have higher risk of exposure to indoor air pollution by Environmental Protection Agency (EPA) standards. Efforts to identify the causes and associations with adverse health effects are needed to ensure that exposure to risks and possible health impacts are mitigated.

Journal of Exposure Science and Environmental Epid↗

USGS2020

Review of studies of composition, toxicology and human health impacts of wastewater from unconventional oil and gas development from shale

Unconventional oil and gas (UOG) extractions has produced large economic benefits. However, prudent management of UOG wastes necessitates a thorough understanding of the complex composition, fate, and potential impacts of wastewater releases. UOG production results in large volumes of wastewater. Despite limited re-use of the wastewater, the majority needs to be disposed of, usually by underground injection. The wastewater contains myriad organic, inorganic, and radioactive substances from hydraulic fracturing and production activities or from the (typically shale) formation. Many substances in this wastewater are either proprietary, or are known or potential toxicants. Limited toxicological studies of these mixtures suggest that some of the components are highly toxic. Thus, any releases of untreated wastewater may represent a threat to environmental integrity and human health.

Book chapter↗

USGS2019

Organic geochemistry and toxicology of a stream impacted by unconventional oil and gas wastewater disposal operations

Water and sediment extracts samples were analyzed for extractable hydrocarbons by gas chromatography/mass spectrometry (GC/MS) using an Agilent (Agilent Technologies, Palo Alto, CA, USA) 7890 series GC and 5975 electron ionization (EI) mass selective detector (MSD) operated in scan mode. Agilent ChemStation software was used for data acquisition and analysis (version E.02.00.493 on GC/MS computer and version F.01.03.2357 on laptop for data workup). A 30 m x 250 m x 0.25 m HP-5MS column (95% dimethyl 5% diphenyl polydimethylsiloxane) was used for GC/MS under the following conditions: 1.0 L splitless injection, constant flow of 0.7 mL/min, solvent delay of 7.5 min, injector temperature of 280C, interface at 300C, temperature program of 50-150C at 7C/min, 150-230C at 6C/min, and 230-300C at 3C/min with mass scanned from 35-500 Da.

West Virginia↗

USGS2015

The continuing medical mystery of Balkan Endemic Nephropathy

Balkan Endemic Nephropathy (BEN) is a disease of subtle onset and insidious progression that typically occurs between the 4th and 6th decade in long‐resident individuals in highly specific geographic locations of the Balkan region and affects 1 – 5% of the population. Though it does not follow typical Mendelian genetics, there is a familial pattern of occurrence. Although residents may live only a few kilometers apart, certain locations are highly affected while others close by, even as close as across the road, remain unscathed. Because of this geographic selectivity scientists have searched for an environmental cause. It is thought that exposure to the toxic plant Aristolochia clematitis is to blame. Genotoxic N‐heterocyclic or polycyclic aromatic containing coal water leachates entering cultivated soil and drinking water are also a possible cause due to the proximity and predictive power of endemic foci to coal deposits. Evidence for Ochratoxin A fungal poisoning also exists. High levels of phthalates have been measured in BEN‐endemic drinking water. BEN is a probably a multifactorial disease that may result from exposure through some of above‐mentioned environmental sources, with genetic factors contributing. This review will discuss recent research concerning the etiology, potential therapies for the treatment of nephropathy, and unexplored research directions for this chronic kidney disease.

Journal of Rare Diseases↗

USGS2014

Atmospheric particulate matter in proximity to mountaintop coal mines: Sources and potential environmental and human health impacts

Mountaintop removal mining (MTM) is a widely used approach to surface coal mining in the US Appalachian region whereby large volumes of coal overburden are excavated using explosives, removed, and transferred to nearby drainages below MTM operations. To investigate the air quality impact of MTM, the geochemical characteristics of atmospheric particulate matter (PM) from five surface mining sites in south central West Virginia, USA, and five in-state study control sites having only underground coal mining or no coal mining whatsoever were determined and compared. Epidemiologic studies show increased rates of cancer, respiratory disease, cardiovascular disease, and overall mortality in Appalachian surface mining areas compared to Appalachian non-mining areas. In the present study, 24-h coarse (>2.5 µm) and fine (≤2.5 µm) PM samples were collected from two surface mining sites in June 2011 showed pronounced enrichment in elements having a crustal affinity (Ga, Al, Ge, Rb, La, Ce) contributed by local sources, relative to controls. Follow-up sampling in August 2011 lacked this enrichment, suggesting that PM input from local sources is intermittent. Using passive samplers, dry deposition total PM elemental fluxes calculated for three surface mining sites over multi-day intervals between May and August 2012 were 5.8 ± 1.5 times higher for crustal elements than at controls. Scanning microscopy of 2,249 particles showed that primary aluminosilicate PM was prevalent at surface mining sites compared to secondary PM at controls. Additional testing is needed to establish any link between input of lithogenic PM and disease rates in the study area.

West Virginia↗

USGS2014

Organic substances in produced and formation water from unconventional natural gas extraction in coal and shale

Organic substances in produced and formation water from coalbed methane (CBM) and gas shale plays from across the USA were examined in this study. Disposal of produced waters from gas extraction in coal and shale is an important environmental issue because of the large volumes of water involved and the variable quality of this water. Organic substances in produced water may be environmentally relevant as pollutants, but have been little studied. Results from five CBM plays and two gas shale plays (including the Marcellus Shale) show a myriad of organic chemicals present in the produced and formation water. Organic compound classes present in produced and formation water in CBM plays include: polycyclic aromatic hydrocarbons (PAHs), heterocyclic compounds, alkyl phenols, aromatic amines, alkyl aromatics (alkyl benzenes, alkyl biphenyls), long-chain fatty acids, and aliphatic hydrocarbons. Concentrations of individual compounds range from < 1 to 100 μg/L, but total PAHs (the dominant compound class for most CBM samples) range from 50 to 100 μg/L. Total dissolved organic carbon (TOC) in CBM produced water is generally in the 1–4 mg/L range. Excursions from this general pattern in produced waters from individual wells arise from contaminants introduced by production activities (oils, grease, adhesives, etc.). Organic substances in produced and formation water from gas shale unimpacted by production chemicals have a similar range of compound classes as CBM produced water, and TOC levels of about 8 mg/L. However, produced water from the Marcellus Shale using hydraulic fracturing has TOC levels as high as 5500 mg/L and a range of added organic chemicals including, solvents, biocides, scale inhibitors, and other organic chemicals at levels of 1000 s of μg/L for individual compounds. Levels of these hydraulic fracturing chemicals and TOC decrease rapidly over the first 20 days of water recovery and some level of residual organic contaminants remain up to 250 days after hydraulic fracturing. Although the environmental impacts of the organics in produced water are not well defined, results suggest that care should be exercised in the disposal and release of produced waters containing these organic substances into the environment because of the potential toxicity of many of these substances.

International Journal of Coal Geology↗