Baseline concentration of total mercury (THg), organic extractable mercury and methylmercury (CH₃Hg) concentrations in sediments from the northeastern, eastern and southeastern parts of the Arabian Gulf were assessed. Surface sediments were collected from eleven stations from the coastal waters of Qatar. All analyses were performed on homogenised samples. Total mercury analysis was performed by Cold Vapour Atomic Absorption Spectrometry (CVAAS), and methylmercury was analysed by Cold Vapour Atomic Fluorescence spectrometry (CVAFS) after aqueous phase ethylation of the extracted samples. Total mercury (THg) in sediments varied from 8.0 μg/kg to 34.3 μg/kg. Methylmercury was detected in all stations and ranged from 1.46 μg/kg to 3.10 μg/kg accounting for 5.4% to 18.4% of total mercury. Total organic carbon (TOC) ranged from 0.16 to 0.72%, while Organic extractable mercury ranged from 1.55 μg/kg to 13.3 μg/kg. Analysis, the grain size within these sediments, was carried out previously paving the way for studying the influence of these parameters on the sedimentary mercury concentration. Speciation was also assessed, as were relations between the measured mercury fractions.

This study examines the empirical effects of four variables: economic growth, energy consumption, foreign direct investment, and financial development on environmental quality in Qatar. Three environmental quality indicators, namely, per capita CO₂ emissions, energy intensity (EI), and Adjusted National Savings (ANS) are used to examine the interactions between the variables using a time series dataset for the period 1980−2016. Following an appropriate multiple structural breaks unit root and cointegration tests, short- and long-run coefficients were estimated through the application of Autoregressive Distributive Lag (ARDL) model. The Toda-Yamamoto (TY) causality test was conducted to determine the causal link, if any, among the variables. Estimated results suggest a detrimental long-run effect of energy consumption on all three indicators of environmental quality. FDI has a negative long-run effect on environmental quality when it is measured by EI only. Financial development has no significant effect on any of the indicators. Bidirectional causality are noted between three variables: economic growth, energy consumption, and financial development and all three indicators of environmental quality. Policy implications are discussed.