Ecotoxicological assessment of cigarette butts on morphology and photosynthetic potential of Azolla pinnata
Garishma Shah, Upma Bhatt, H. G. Singh, Deepak Kumar, Jyotshana Sharma, Reto J. Strasser, Vineet Soni
Abstract
Abstract Cigarette butts (CBs) have become the most ubiquitous form of anthropogenic litter globally. CBs contain various hazardous chemicals that persist in the environment for longer period. These substances are susceptible to leaching into the environment through waterways. The recent study was aimed to evaluate the effects of disposed CBs on the growth and development of Azolla pinnata , an aquatic plant. It was found that after a span of 6 days, the root length, surface area, number of fronds, and photosynthetic efficacy of plant were considerably diminished on the exposure of CBs (concentrations 0 to 40). The exposure of CBs led to a decrease in the F M , F V /F 0 , and φP 0 , in contrast, the φD 0 increased in response to CBs concentration. Moreover, ABS/CSm, TR 0 /CSm, and ET 0 /CSm displayed a negative correlation with CB-induced chemical stress. The performance indices were also decreased ( p -value ≤ 0.05) at the highest concentration of CBs. LD 50 and LD 90 represent the lethal dose, obtained value for LD 50 is 20.30 CBs and LD 90 is 35.26 CBs through probit analysis. Our results demonstrate that the CBs cause irreversible damage of photosynthetic machinery in plants and also reflect the efficacy of chlorophyll a fluorescence analysis and JIP test for assessing the toxicity of CBs in plants.