Benzene: A critical review on measurement methodology, certified reference material, exposure limits with its impact on human health and mitigation strategies.

Benzene is a carcinogenic pollutant with significant emission sources present in the atmosphere. The need for accurate and precise measurement of benzene in the atmosphere has become increasingly evident due to its toxicity and the adverse health effects associated with exposure to different concentrations. Certified reference material (CRM) is essential to establish the traceability of measurement results.

Source contribution of black carbon aerosol during 2020-2022 at an urban site in Indo-Gangetic Plain.

The extensive emissions of black carbon (BC) from the Indo-Gangetic Plain (IGP) region of India have been well recognized. Particularly, biomass emissions from month-specific crop-residue burning (April, May, October, November) and heating activities (December-February) are considered substantial contributors to BC emissions in the IGP. However, their precise contribution to ambient BC aerosol has not been quantified yet and remains an issue of debate.

Comparative measurement of CO, CH and CO at two traffic interjunctions having inflated vehicular flow in Delhi.

Vehicular emissions are considered one of the major anthropogenic sources of greenhouse gases and poor air quality in metropolitan cities. This study aims to see the correlation of CO, CH, and CO through monitoring over a period from December 2020 to October 2021 covering three seasons' winter, summer, and monsoon at two different traffic locations of Delhi having different traffic volumes, road patterns, and traffic management. The annual average morning concentration of CO, CH and CO was found (533 ± 105), (7.

Seasonal and diurnal measurement of ambient benzene at a high traffic inflation site in Delhi: Health risk assessment and its possible role in ozone formation pathways.

Benzene is the most toxic and hazardous pollutant among volatile organic compounds (VOCs), as it comes under group 1 carcinogens recognized by the International Agency for Research on Cancer (IARC). It also plays a significant role in forming secondary pollutants like ozone. The benzene concentration was measured using a charcoal sorbent tube by active sampling at a traffic junction and analysis was done using GC-FID.

Physical and chemical properties of PM in Delhi: A comparison between clean and polluted days.

Considering the significance of PM aerosol in assessing health impacts of air pollution, an extensive analysis of PM samples collected at an urban site in Delhi is presented in this study. Overall, PM contributed to about 50 % of PM mass which is alarming especially in Delhi where particle mass loadings are usually higher than prescribed limits. Major portion of PM consisted of organic matter (OM) that formed nearly 47 % of PM mass.

Quantifying uncertainty in measurement of mercury in suspended particulate matter by cold vapor technique using atomic absorption spectrometry with hydride generator.

As a result of rapid industrialization several chemical forms of organic and inorganic mercury are constantly introduced to the environment and affect humans and animals directly. All forms of mercury have toxic effects; therefore accurate measurement of mercury is of prime importance especially in suspended particulate matter (SPM) collected through high volume sampler (HVS). In the quantification of mercury in SPM samples several steps are involved from sampling to final result.

Evaluation of purity with its uncertainty value in high purity lead stick by conventional and electro-gravimetric methods.

Background: A conventional gravimetry and electro-gravimetry study has been carried out for the precise and accurate purity determination of lead (Pb) in high purity lead stick and for preparation of reference standard. Reference materials are standards containing a known amount of an analyte and provide a reference value to determine unknown concentrations or to calibrate analytical instruments. A stock solution of approximate 2 kg has been prepared after dissolving approximate 2 g of Pb stick in 5% ultra pure nitric acid.

Antibacterial activity of some unsymmetrical diorganyltellurium(IV) dichlorides.

Six unsymmetrical diorganyltellurium(IV) dichlorides RR'TeCl2 (where R= phenacyl-, 1-naphthacyl-, and styrylacyl- and R' = p-methoxyphenyl, p-hydroxyphenyl-, and 3-methyl-4-hydoxyphenyl-) were tested for their antibacterial activity against gram-positive (Bacillus subtilis ATCC 6633 and Staphylococcus aureus ATCC 25923) and gram-negative (Escherichia coli ATCC 25922. Pseudomonas aeruginosa ATCC 27853 and Salmonella sp.) bacteria.