Environmental forensic analysis of the microplastic pollution at “Nattika” Beach,Kerala Coast,India

Abstract

Kerala, being a prominent tourist destination in the southern part of India with a coastline of 560?km, is prone to microplastic pollution. The National Oceanic and Atmospheric Administration (NOAA) of the USA defines microplastics as plastics of size < 5?mm–1?nm. To solve the problem of microplastic pollution, it is essential to track its source. As plastics are pervasive, it is challenging to track its source with a level of certainty required for implementing control strategies. Formulating and adopting suitable environmental forensic techniques to track microplastic pollution become important in this context. This study quantified the microplastic pollution of the Nattika coast, Kerala, India, and devised an environmental forensic investigation strategy for identifying the pathways and sources of microplastics. The microplastics of size 5–1?mm only were considered. The number of microplastics found in the Nattika Beach in 2017 and 2018 was 70.15 items kg^?1 of sand and 120.85 items kg^?1 of sand, respectively. The microplastics were subjected to analysis in FTIR and SEM as part of characterization. The forensic investigation of the pollution indicated that majority of the microplastic is sourced from the site/nearby area. The investigation could draw useful conclusions regarding the pathways of pollution. The fibrous microplastic, a significant component in the sample, was found to be sourced from the fishing net mending activities carried out close to the shore.     

An environmental forensic investigation at a bio-medical waste treatment and disposal facility in Kerala,India

Indian statutes identify twelve different types of biomedical wastes and give the treatment and disposal options for each. Since it is not possible for every generator of biomedical waste to go for their own treatment and disposal facility, the small-scale generators take the service of centralized treatment and disposal facilities available to them on payment. In the state of Kerala in India, where the basic health indicators match those of many developed countries, the centralized biomedical waste treatment facility is run by Indian Medical Association (IMA), Kerala, under the banner IMAGE (IMA Goes Eco-Friendly) at a place called “Kanjikode” in the Palakkad District. The facility receives biomedical waste from around 4500 hospitals across the State and an equal number of medical laboratories. The plant incinerates the incinerable waste and the other kind of waste are disinfected and decontaminated. The residual ash and dried sludge are then moved to the landfill area. Recently, the facility was in the middle of a controversy due to the alleged health hazards it posed to the surrounding population. An environmental forensic investigation was carried out at the site to establish the merits of the allegation. The reported study is a part of the investigation where groundwater was analysed for the presence of heavy metals. As the biomedical waste contain heavy metals like Zn, Pb, Cd, Cr, and Hg, the presence of these were analysed to establish contamination of groundwater by the facility. The study area is bounded by Malampuzha dam and Korayar river. Groundwater contaminant transport modelling was done for a 3430 m × 3960 m area surrounding the waste treatment facility using Visual MODFLOW and MODPATH. Ground water flow direction and particle pathlines were computed to track the movement of contaminants. Groundwater samples were collected from the area shown to be polluted by the model, if metals were discharged by the facility, and also from outside this area. Water samples were collected conforming to the guidelines in the “Pollution Crime Forensic Investigation Manual” published by INTERPOL. The collected water samples were tested for heavy metal concentration using atomic absorption spectroscopy (AAS). The water sample analysis showed that the groundwater is not contaminated by heavy metal discharge from the biomedical treatment facility.     

Use of DNA barcoding to reveal species composition of convenience seafood

Increased education of consumers can be an effective tool for conservation of commercially harvested marine species when product labeling is accurate and allows an informed choice. However, generic labeling (e.g., as white fish or surimi) and mislabeling of seafood prevents this and may erode consumer confidence in seafood product labels in general. We used DNA barcoding to identify the species composition of two types of convenience seafood (i.e., products processed for ease of consumption): fish fingers (long pieces of fish covered with bread crumbs or batter, n = 241) and seafood sticks (long pieces of cooked fish, n = 30). In products labeled as either white fish or surimi, four teleost species were present. Less than 1.5% of fish fingers with species-specific information were mislabeled. Results of other studies show substantially more mislabeling (e.g., >25%) of teleost products, which likely reflects the lower economic gains associated with mislabeling of convenience seafood compared with whole fillets. In addition to species identification, seafood product labels should be required to contain information about, for example, harvesting practices, and our data indicate that consumers can have reasonable confidence in the accuracy of the labels of convenience seafood and thus select brands on the basis of information about current fisheries practice.     

Understanding the source of water for selected springs within Mojave Trails National Monument,California

While water sources that sustain many of the springs in the Mojave Desert have been poorly understood, the desert ecosystem can be highly dependent on such resources. This evaluation updates the water resource forensics of Bonanza Spring, the largest spring in the southeastern Mojave Desert. The source of spring flow at Bonanza Spring was evaluated through an integration of published geologic maps, measured groundwater levels, water quality chemistry, and isotope data compiled from both published sources and new samples collected for water chemistry and isotopic composition. The results indicate that Bonanza Spring has a regional water source, in hydraulic communication with basin fill aquifer systems. Neighboring Lower Bonanza Spring appears to primarily be a downstream manifestation of surfacing water originally discharged from the Bonanza Spring source. Whereas other springs in the area, Hummingbird, Chuckwalla, and Teresa Springs, each appear to be locally sourced as “perched” springs. These conclusions have important implications for managing activities that have the potential to impact the desert ecosystem.     

Predicting Sample Source Location from Soil Analysis Using Neural Networks

A system combining a national soils database with a neural network was developed for prediction of source location for soil samples. The neural network was trained to predict environmental characteristics, which can be of crucial importance to investigating officers in a police operation or to environmental agencies attempting to locate the source of a pollutant. When coupled with maps of environmental conditions and a generalized opinion pool approach, the system was used to produce weighted maps of source location. The system was capable of reducing search areas of a sample source to less than 0.1% of the total area.     

Pyrolysis-GC-MS analysis of crude and heavy fuel oil asphaltenes for application in oil fingerprinting

A Pyrolysis – Gas Chromatography – Mass Spectrometry (Py-GC-MS) method was developed for the analysis and profiling of crude and heavy fuel oil asphaltenes, for application in oil fingerprinting. Asphaltenes were precipitated from ten geographically different oils using n-pentane, and analysed by Py-GC-MS. Alkane profiles and sulphur/aromatic profiles were used to compare the oils, and to correctly differentiate oils from different geographical regions. Py-GC-MS could not differentiate a weathered oil sample and a fresh oil sample from the same source. The results of this study support the findings from a previously developed FTIR method for asphaltene profiling.