t. The present experiment was done to evaluate the impact of ambient air pollution on carrot
(Dacus carota var. Pusa Kesar) plants using open top chambers (OTCs) ventilated with ambient
(NFCs) or charcoal filtered air (FCs) at a suburban site of Varanasi, India. Various morphological,
physiological and biochemical characteristics of the plants were studied at different growth stages.
Air monitoring data clearly showed high concentrations of SO2, NO2 and O3 in the ambient air of
study site. SO2 and NO2 concentrations were higher during early growth stages of carrot, whereas O3
concentration was highest during later growth stages. Filtration of air has caused significant reductions
in all the three pollutant concentrations in FCs as compared to NFCs.
Plants growing in FCs showed significantly higher photosynthetic rate, stomatal conductance, water
use efficiency and variable fluorescence as compared to plants growing in NFCs. Protein content also
showed a similar pattern, however, lipid peroxidation, ascorbic acid content and peroxidase activity
were higher in plants growing in NFCs as compared to FCs. Shoot length, number of leaves per
plant, leaf area and root and shoot weight increased significantly upon filtration of ambient air. Total
nitrogen decreased significantly in root, but increased significantly in shoot of plants grown in NFCs.
Total P, Mg, Ca and K contents decreased significantly in plants grown in NFCs as compared to
FCs. The individual pollutant concentrations were below threshold for plant injury, but the combined
effect of all the three seems to act synergistically in causing greater adverse impact on dry weight
and physiology of carrot plants. The study clearly indicates that air pollutants are high enough in the
ambient air to cause significant unfavorable impact on carrot plants. The work further supports the
usefulness of OTCs for assessing air pollution damage under field conditions in developing countries.

Rapid growth in urbanization and industrialization in developing countries may significantly contribute in heavy metal contamination of vegetables through atmospheric depositions. In the present study, an assessment was made to investigate the spatial and seasonal variations in deposition rates of heavy metals and its contribution to contamination of palak (Beta vulgaris). Samples of bulk atmospheric deposits and Beta vulgaris for analysis of Cu, Zn, Cd and Pb were collected from different sampling locations differing in traffic density and land use patterns. The results showed that the sampling locations situated in industrial or commercial areas with heavy traffic load showed significantly elevated levels of Cu, Zn and Cd deposition rate as compared to those situated in residential areas with low traffic load. The deposition rates of Cu, Zn and Cd were significantly higher in summer and winter as compared to rainy season, however, Pb deposition rate was significantly higher in rainy and summer seasons as compared to winter season. Atmospheric depositions have significantly elevated the levels of heavy metals in B. vulgaris collected during evening as compared to those collected in morning hours. The study further showed that local population has maximum exposure to Cd contamination through consumption of B. vulgaris. The present study clearly points out the urban and industrial activities of a city have potential to elevate the levels of heavy metals in the atmospheric deposits, which may consequently contaminate the food chain and thus posing health risk to the local population.