Screening and prioritization of nano- and microplastic particle toxicity studies for evaluating human health risks – development and application of a toxicity study assessment tool

Concern regarding the human health implications that exposure to nano- and microplastic particles (NMPs) potentially represents is increasing. While there have been several years of research reporting on the ecotoxicological effects of NMPs, human health toxicology studies have only recently emerged. The available human health hazard data are thus limited, with potential concern regarding the relevance and reliability for understanding the potential human health implications. In this study we develop and apply a NMP toxicity screening assessment tool (NMP-TSAT) for evaluating human health effects studies against a suite of quality assurance and quality control (QA/QC) criteria for both in vivo and in vitro studies. A total of 74 studies representing either inhalation or oral exposure pathways were identified and evaluated. Assessment categories include particle characterization, experimental design, and applicability for risk assessment; with critical and non-critical criteria organized to allow screening and prioritization. It is observed that the majority of studies evaluated using the NMP-TSAT have been performed on monodisperse particles, predominately spheres (≈60%), consisting of polystyrene (≈46%). The majority of studies have tested particles < 5 μm, with a minimal particle size of 10 nm and a maximum particle size of about 200 μm. The total assessment score (TAS) possible for in vivo studies is 52, whereas for in vitro studies it is 46, which is based on receiving a maximum score of 2 against 26 and 23 criteria, respectively. The evaluated TAS ranged from between 12 and 44 and 16–34, for in vivo and in vitro studies, respectively. Given the challenges associated with prioritizing studies based on ranking them according to their TAS we propose a Tiered approach, whereby studies are initially screened based on how they score against various critical criteria, which have been defined for their relevance for assessing the hazards and risks for human health. In this instance, studies that score a minimum of ‘1’ against each of the critical criteria, regardless of how they rank according to their TAS, are prioritized as part of a Tier 1 screening and prioritization phase, which would then be followed by an expert evaluation, representing a Tier 2 level of assessment. Using this approach we identify 10 oral ingestion and 2 inhalation studies that score at least 1 against all critical criteria. Lastly, several key observations for strengthening future effects studies are identified, these include a need for the generation and access to standard reference materials representative of human exposure to NMPs for use in toxicity test systems and/or the improved characterization and verification of test particle characteristics, and the adoption of study design guidance, such as recommended by OECD, when conducting either in vivo inhalation or oral ingestion toxicity tests.

Understanding electricity nightmare and health implications among slum dwellers in Ghana

PurposeThe purpose of the study was to examine the electricity challenges confronting slums in order to understand the health implications thereof.Design/methodology/approachThe study utilized purposive sampling techniques supported by the convenience sampling method within the context of qualitative research to select 30 interviewees of varying demographics for in-depth interviews.FindingsThe findings revealed that slums faced various forms of challenges that are attributable to lack of government support, stringent procedures and financial hardship, among others. The study also found that a lack of health education in the slums has resulted in health problems, such as skin diseases, stomach aches, cholera, typhoid and childbirth complications.Research limitations/implicationsThe outcome of this study cannot be generalized to represent the whole population of slums within context due to the qualitative approach.Practical implicationsThe study advanced the frontiers of slum literature to understand contextual issues that are important to policymakers and practitioners.Originality/valueThis study revealed a country-specific understanding of the challenges confronting slum dwellers in accessing electricity through the perspective of the two-factor theory of motivation.

Potentially harmful materials in the feces of wild ring-tailed coatis (Nasua nasua) and health implications

ABSTRACT: In ecological parks, the proximity to tourist activities facilitates the exploration of garbage by coatis, with possible serious consequences for the animals health . We described the contents of wild coatis feces from three ecological parks. After analyzing 62 samples, fragments of plants and animals were identified in all feces. In the feces of two parks, seeds were present between 36.4% and 48.6% of the samples. Arthropod fragments were identified in 100% of the samples from two parks, but only 87.3% in a third park. Scales, bones or bird feathers were present in some samples. Undigested material of industrial origin was detected in 34.3% to 54.5% of the samples, such as fragments of paper, string, plastic, aluminum, latex and glass. Results are in line with other studies on the diet of wild coatis, but the intake of foreign bodies, potentially harmful to health, is described for the first time. Clinical problems resulting from ingesting waste can be dental fractures, mucosal erosions, intestinal perforation, peritonitis, impaction, diarrhea, weight loss, intoxication and infections. Coatis in the three parks are at risk of health, and actions are needed to avoid clinical and potentially fatal problems. Four actions are recommended to avoid ingesting foreign bodies: increasing the environmental education of visitors; improving the storage of waste generated in parks; periodically monitor the health of coatis, in order to make interventions when possible; make a permanent program to study the ecology of species in the three parks.

Release of microplastic fibres and fragmentation to billions of nanoplastics from period products: preliminary assessment of potential health implications

Health effects related to the plastic content of disposable period products have not been recognized or scientifically addressed. To begin to understand their potential impact on the environment and human...

Seabird Tissue Archival and Monitoring Project (STAMP) Data from 1999-2010

The multi-entity, long-term Seabird Tissue Archival and Monitoring Project (STAMP) has collected eggs from various avian species throughout the North Pacifc Ocean for over 20 years to create a geospatial and temporal record of environmental conditions. Over 2,500 samples are currently archived at the NIST Biorepository at Hollings Marine Laboratory in Charleston, South Carolina. Longitudinal monitoring efforts of this nature provide invaluable data for assessment of both wildlife and human exposures as these species often consume prey (e.g., fish) similar to, and from sources (e.g., oceanic) comparable to, human populations nearby. In some areas, seabird eggs also comprise a signifcant part of subsistence diets providing nutrition for indigenous peoples. Chemometric profles and related health implications are known to differ across species. Eggs, however, can be diffcult to assign to a species unless the bird is observed on the nest from which the sample was collected due to similar appearance within a genus and sympatric nesting behavior. This represents a large point of uncertainty for both wildlife managers and exposure researchers alike.