Spatio-temporal variation and ecological risk assessment of microplastics along the touristic beaches of a mediterranean coast transect (Valencia province, East Spain)

Annually, the Mediterranean region attracts around one-third of the global coastal tourism, which is acknowledged as a substantial contributor to plastic pollution. Coastal municipalities mitigate this through periodic sand and shore cleaning. However, the efficacy of these measures remains uncertain. In this study, the occurrence of MPs (10 μm-5 mm) in sand from seven different, regularly cleaned, touristic beaches of the coastline of Valencia province (E Spain) was assessed. Two different sampling campaigns were performed in winter and in summer (2022) to compare the results and understand the influence of the high touristic activity, as well as, the efficiency of the measures taken against MPs pollution. The methodology used was designed specifically for the matrix and employed density separation using a Sediment Microplastic Isolation (SMI) Unit. In addition to conventional visual inspection and ATR-FTIR, automatic quantification and identification of the polymers of lower size was performed by μFTIR. The average MPs concentration in the summer (339 ± 92 MP kg-1 by stereomicroscopy and 339 ± 189 MP kg-1 by μFTIR) was significantly higher than in the winter (71 ± 92 MP kg-1 and 143 ± 85 MP kg-1) (p < 0.05). The combination of these analytical tools provides comprehensive information about the MPs present in beach sand. Fibers were the most abundant form of MPs, while most of the polymers analyzed were polyethylene (PE) and halogenated polystyrene (Cl-PS and Br-PS) with food packaging, swimming equipment and fishing nets being their most probable sources. Ecological risk assessment was performed through the Pollution Load Index (PLI), the Hazardous Index (HI) and the Risk Quotient (RQ), with the results indicating potential risk that ranges from moderate to high depending on the applied approach.

Plastic pollution as a novel reservoir for the environmental survival of the drug resistant fungal pathogen Candida auris

The WHO recently classified Candida auris as a fungal pathogen of "critical concern". Evidence suggests that C. auris emerged from the natural environment, yet the ability of this pathogenic yeast to survive in the natural environment is still poorly understood. The aim of this study, therefore, was to quantify the persistence of C. auris in simulated environmental matrices and explore the role of plastic pollution for facilitating survival and potential transfer of C. auris. Multi-drug resistant strains of C. auris persisted for over 30 days in river water or seawater, either planktonically, or in biofilms colonising high-density polyethylene (HDPE) or glass. C. auris could be transferred from plastic beads onto simulated beach sand, particularly when the sand was wet. Importantly, all C. auris cells recovered from plastics retained their pathogenicity; therefore, plastic pollution could play a significant role in the widescale environmental dissemination of this recently emerged pathogen.

Detection of enteric viruses and SARS-CoV-2 in beach sand

Beach sand harbors a diverse group of microbial organisms that may be of public health concern. Nonetheless, little is known about the presence and distribution of viruses in beach sand. In this study, the first objective was to evaluate the presence of seven viruses (Aichi virus, enterovirus, hepatitis A virus, human adenovirus, norovirus, rotavirus, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) in sands collected at public beaches. The second objective was to assess the spatial distribution of enteric viruses in beach sand. To that end, 27 beach sand samples from different beaches in Portugal were collected between November 2018 and August 2020 and analyzed for the presence of viruses. At seven beaches, samples were collected in the supratidal and intertidal zones. Results show that viruses were detected in 89 % (24/27) of the sand samples. Aichi virus was the most prevalent (74 %). Noroviruses were present in 19 % of the samples (norovirus GI - 15 %, norovirus GII - 4 %). Human adenovirus and enterovirus were detected in 48 % and 22 % of the samples, respectively. Hepatitis A virus and rotavirus were not detected. Similarly, SARS-CoV-2 in beach sand collected during the initial stages of the pandemic was also not detected. The detection of three or more viruses occurred in 15 % of the samples. Concentrations of viruses were as high as 7.2 log copies (cp)/g of sand. Enteric viruses were found in higher prevalence in sand collected from the supratidal zone compared to the intertidal zone. Human adenovirus was detected in 43 % of the supratidal and 14 % in the intertidal samples and Aichi virus in 57 % and 86 % of the intertidal and supratidal areas, respectively. Our findings suggest that beach sand can be a reservoir of enteric viruses, suggesting that it might be a vehicle for disease transmission, particularly for children, the elderly, and immunocompromised users.

Radioactivity concentration and radiological risk assessment of beach sand along the coastline in the Mediterranean Sea

A radiological baseline survey was conducted using a calculation analysis to assess the 226Ra, 232Th, 40K, and 137Cs distribution in beach sand samples collected from the coastal areas of the Mediterranean Sea. An analysis of the activity concentration of selected radionuclides was conducted. No evidence of recent migration of radiocaesium was found through precipitation, as well as indirect pathways, such as ocean runoff. The activity concentration of 226Ra, 232Th, 40K and 137Cs in beach sands ranged from 12 ± 1 to 37 ± 4 Bq kg- 1 (mean of 26 ± 3 Bq kg- 1); 18 ± 2 to 71 ± 8 Bq kg- 1 (mean of 40 ± 5 Bq kg- 1); 411 ± 10 to 720 ± 16 Bq kg- 1 (mean of 572 ± 12 Bq kg- 1); and 0.8 ± 0.1 to 3.1 ± 0.6 Bq kg- 1 (mean of 1.9 ± 0.3 Bq kg- 1), respectively. The radiological risk assessment showed that in all cases the values were lower than those that endanger life and safe work.

Macro- and microplastic abundance from recreational beaches along the South Aegean Sea (Türkiye)

This study aimed to evaluate the abundance and diversity of macro- and microplastics in sand samples collected during summer and winter from eight different beaches used for recreational purposes located on the South Aegean coasts of Türkiye. According to the results, microplastic in fiber shape was dominant on all the beaches. The highest microplastic abundance was determined at Ölüdeniz Kumburnu Beach (360.00 ± 237.66 particles kg-1 dw) in summer and at Aktur Beach (358.33 ± 397.24 particles kg-1 dw) in winter. A significant positive correlation was found in the winter between microplastic amounts and wind speed. The study area is an important touristic center faraway from major cities and industrial areas. Thus, plastic pollution in this area may be the result of tourism activities in the summer, discharge waters from wastewater treatment plants or transportation by meteorological factors (like waves, wind or river flows).

Evaluation of radioactivity in soil and rock samples from an undiscovered sea beach in the southeastern coastline of Bangladesh and associated health risk

This study marks the first-ever assessment of radiological hazards linked to the sands and rocks of Patuartek Sea Beach, situated along one of the world's longest sea beaches in Cox' Bazar of Bangladesh. Through the utilization of an HPGe detector, a comprehensive analysis of the activity concentrations of 226Ra, 232Th, and 40 K was conducted, and their activity ranged from 7 to 23 Bq/kg, 9-58 Bq/kg, and 172-340 Bq/kg, respectively, in soils, and 19-24 Bq/kg, 27-39 Bq/kg, and 340-410 Bq/kg, respectively, in rocks. Some sand samples exhibited elevated levels of 232Th, while the rock samples displayed higher levels of 40 K compared to the global average. The radiological hazard parameters were assessed, and no values surpassed the recommended limits set by several international organizations. Hence, the sands and rocks of Patuartek sea beach pose no significant radiological risk to the residents or tourists. The findings of this study provide crucial insights for the development of a radiological baseline map in the country, which is important due to the commissioning of the country's first nuclear power plant Rooppur Nuclear Power Plant. The data may also stimulate interest in the rare-earth minerals present in the area, which is important for the electronics industry, thorium-based nuclear fuel cycles.

Diversity and Dynamics of Marine Arenicolous Fungi in Three Seasides of the Korean Peninsula

Various arenicolous fungal species have been detected from the beach sand in the coastal area. However, little has been revealed regarding their distribution and dynamics. To investigate the overall diversity of marine arenicolous fungi (MAFs) in Korea and whether the composition of MAFs is affected by ocean currents, we isolated and analyzed the fungal community from the western, southern, and eastern seasides of the Korean Peninsula. In total, 603 strains were isolated and identified as 259 species based on appropriate molecular markers for each genus (ITS, BenA, CaM, tef1, and act). The composition of MAFs showed differences among the seasides. Our results indicate that many MAFs inhabit the beach sand on the Korean Peninsula, and the composition of MAFs is also affected by ocean currents flowing along each coast.

Occupational exposure to mercury from cinnabar enriched sand in workers of Grado Beach, Gulf of Trieste (North-eastern Italy, upper Adriatic Sea)

Health and safety of occupations entailing extensive skin contact with cinnabar-enriched sand in beaches of Friuli-Venezia Giulia (FVG) Region (North-eastern Italy) have been questioned for possible skin absorption of mercury (Hg). One hundred mg hair was collected from the occipital scalp of 50 male workers of Grado beach and 121 males from FVG general population. Factors associated with hair Hg content were investigated by multivariable logistic (considering Hg levels >1 vs ≤1 mg/kg) and log-transformed linear regression. The median hair concentration of Hg in male beach workers was 0.70 (IQR = 0.42; 1.34) mg/kg, lower than FVG general population's [1.29 (IQR = 0.87-2.06) mg/kg (p < 0.001)]. In both regression models the hair Hg increased with fish consumption, both among beach workers of Grado and FVG general population. The mean Hg levels in beach workers of Grado fell within an acceptable range, not requiring restrictions of their occupational activities.

Radioactive risk assessment of beach sand along the coastline of Mediterranean Sea at El-Arish area, North Sinai, Egypt

Beach sand includes various levels of natural radioactivity, which can cause health effects. The natural radioactivity was measured in the beach sand along the coastline of the Mediterranean Sea at the east of the El-Arish area, Egypt. Using the HPGe spectrometer, the contribution of radionuclides ²²⁶Ra, ²³²Th and ⁴⁰K in the gamma emitted radiation illustrated that the ²²⁶Ra, ²³²Th and ⁴⁰K activity concentrations are 8.8 ± 3.9, 30.8 ± 12.2 and 106.9 ± 46.8 Bq kg^-1, respectively, which is lower than the reported worldwide limit 33, 45 and 412 Bq kg^-1. The radioactive hazards associated with the beach sand along the coastline of the Mediterranean Sea at the east of the El-Arish area were investigated. The obtained results among the radiological hazard parameters, the radium equivalent content (Ra_eq), the absorbed dose rate (D_air), annual effective dose (AED), external (H_ex) and internal (H_in) hazard indices were estimated. Moreover, the excess lifetime cancer risk (ELCR) and the annual gonadal dose equivalent (AGDE) were also computed and illustrated their values less than the recommended levels. Multivariate statistical approaches like Pearson correlation, the principal component analysis (PCA) and the hierarchical cluster analysis (HCA) were applied to investigate the correlation between the radionuclides and the corresponding radiological hazard variables. Based on the statistical analysis, the ²²⁶Ra and ²³²Th mainly contribute to the radioactive risk of beach sand. Finally, no significant risk of the public associated with utilizing beach sand in building materials.

Radiological monitoring in some coastal regions of the Saudi Arabian Gulf close to the Iranian Bushehr nuclear plant

We studied the concentrations of terrestrial and anthropogenic radionuclides in seawater and shore sediment/sand of three selected regions; Khafji, Safaniyah and Menifah along the Saudi Arabian Gulf coast. The mean activity concentrations of the ²²⁸Ra, ²²⁶Ra, and ⁴⁰K in the analyzed sand samples are 5.9, 3.5 and 113.5 Bq/kg, and the respective values in seawater samples are 1.6, 0.8 and 10.4 Bq/L. All data show lower than the corresponding UNSCEAR (2000) reported world average values of 35, 30 and 400 Bq/kg for soil matrix. A few relevant radiological hazards were quantified by the estimation of the absorbed dose rate, and the results are compared with the prescribed limits set by international regulatory bodies. Measured data indicates that the studied coastal regions pose a negligible radiological hazards to the public, and show an insignificant radioactive loading to this coastal region by the Busher nuclear power plant.

Microplastic pollution in surface seawater and beach sand from the shore of Rayong province, Thailand: Distribution, characterization, and ecological risk assessment

The distribution, characteristics, and ecological risk of microplastics in beach sand and seawater samples collected along the shore of Rayong province, Thailand, were investigated in this study. The average microplastics abundance in beach sand and seawater was 338.89 ± 264.94 particles/kg d.w. and 1781.48 ± 1598.36 particles/m³, respectively. Beach sand and seawater had the most yellow-brown particles and transparent microfibers, respectively. The most common microplastics (100-500 μm) and polyethylene were found. In beach sand, the potential ecological risk (RI) is classified as minor, while in seawater, it is classified as medium. The PLI_zone in beach sand and seawater was Hazard Level II and Hazard Level IV, respectively. Despite their apparent proximity, the non-correlation between risk levels in beach sand and seawater may be due to polymer type variations influenced by the different land-based and sea-based sources.

UV filters and UV stabilisers adsorbed in microplastic debris from beach sand

Microplastics (MPs) in oceans adsorb different types of pollutants, which can negatively impact the food chain. The extensive use of personal care products (PCPs) has led to their ubiquitous environmental presence, and their partition between plastic matrices and surroundings is determined by their physico-chemical characteristics and environmental conditions. This work develops and applies a methodology to determine 12 UV filters (UVFs) and UV stabilisers (UVSs) in MPs collected in beach sand. The analyses were carried out by ultrasound-assisted extraction and ultrahigh-performance liquid chromatography with tandem mass spectrometry detection. The validated procedure was applied to MPs samples taken in sand samples from 13 beaches on the Canary Islands (Spain). The results showed the presence of 10 UV filters and UV stabilisers at concentrations between 1 and 4031 ng·g^-1, where octocrylene was the most frequently found. The target analytes were present in all the sampling beaches.

Testing the factors controlling the numbers of microplastics on beaches along the western Gulf of Thailand

Microplastic pollution is one of the most significant global environmental concerns. This study represents a first attempt to establish connections between the concentration of microplastics and both ocean surface circulation direction and land-based sources along the western Gulf of Thailand. Microplastics at the high-tide line from 25 beaches in 5 provinces were quantified. Observed amounts range from 20 to 273 (max. 5741) pieces/kg. Sheets were the most common shape and black the most common color of microplastics. Our study showed a significant, positive correlation between the number of microplastics and land-based sources (e.g., aquatic industries). While human activities were the dominant factor affecting microplastic concentrations, the newly designed surface circulation direction (SCD) index reflected relative changes in microplastic amounts. Our study identified several locations with substantial microplastic pollution which require a proper management system with appropriate laws and regulations, and a public awareness campaign about effects of microplastics on ecosystems.

Analysis of the occurrence of microplastics in beach sand on the Brazilian coast

The occurrence of microplastics in coastal areas is a growing concern due to the increase in plastic waste pollution in recent decades. This study had as objective to evaluate the occurrence of microplastics in Brazilian beach sand, using a simple and fast methodology. In addition, possible microplastics were classified according to color, shape and chemical composition. The study was conducted on six beaches on the Brazilian coast: Pecado Beach (RJ), Castanheiras Beach (ES), Regência Beach (ES), Imbassaí Beach (BA), Viral Beach (SE) and Ponta dos Mangues Beach (SE). The methodology was adapted from international protocols, with section demarcation (100 m), where samples were collected from the superficial layer of the beach sand in ten quadrants (50 cm × 50 cm). The laboratory extraction procedure consisted of the density separation technique in two stages: the first used sodium chloride solution and the second used zinc chloride solution. For the visual inspection and screening procedures, a stereoscopic microscope was used. A total of 166 items of microplastics were collected on the six beaches on the Brazilian coast under study. The largest quantity of possible microplastics was recorded on the beaches of Viral (SE) and Ponta dos Mangues (SE) with 30.4 items/m² and 17.4 items/m², respectively. Regarding colour, white items were predominant (49.3%), and among particle types, fragments represented 85.1%. In addition, some microplastic particles were sent for FT-IR analysis, one of which was identified as being polyethylene. This study contributes to the knowledge of the presence of microplastics in different locations, and to supporting decision makers regarding coastal management.

Multivariate statistical approach on distribution of natural and anthropogenic radionuclides and associated radiation indices along the north-western coastline of Aegean Sea, Greece

A comprehensive radiological survey using multivariate statistical analysis was carried out to evaluate the distribution of ⁴⁰K, ²³²Th, ²²⁶Ra, ²³⁵U, and ¹³⁷Cs, and associated radiation indices in beach sand samples of the coastal area of the Aegean Sea. The activity concentration of selected radionuclides was measured and no clue of recent migration of radiocaesium by not only precipitation but also through an indirect way, such as ocean runoff, was found. As part of radiological risk assessment, external radiation hazard index, radium equivalent activity, effective dose, and absorbed dose rate were estimated. Pearson correlation, cluster, and PCA analysis were used by processing observed radiological parameters to determine the correlation between the radiological parameters and locations. Pearson correlation shows a strong association between all parameters and activity of ²²⁶Ra and ²³²Th. A spatial distribution map was provided to a distinct visual representation of the distribution of radionuclide contents in the study area.

Taxonomic and functional analyses reveal existence of virulence and antibiotic resistance genes in beach sand bacterial populations

Coastal sands are important natural recreational facilities that have become hotspots for tourism and economic development. However, these sands harbour diverse microbial assemblages that play a critical role in the balance between public health and ecology. In this study, targeted high-throughput sequencing analysis was used to identify sand-borne bacterial populations at four public beaches in Durban. The effect of heavy metal in shaping the distribution of bacterial metacommunities was determined using canonical correspondence analysis (CCA), while the functional gene profiles were predicted using PICRUSt2 analysis. Sequences matching those of the bacterial phylum Proteobacteria were the most abundant in all samples, followed by those of the phyla Firmicutes, Actinobacteria, Bacteroidetes, and Gemmatimonadetes. Genus-level taxonomic analysis showed the presence of 1163 bacterial genera in all samples combined. The distribution of bacterial communities was shaped by heavy metal concentrations, with the distribution of Flavobacteria, Bacteroidia, and Deltaproteobacteria influenced by Pb and Zn, while B and Cr influenced the distribution of Clostridia and Gammaproteobacteria, respectively. Identified antibiotic resistance genes included the peptidoglycan biosynthesis gene II, III, IV, and V, as well as the polymyxin resistance gene, while the virulence genes included the sitA, fimB, aerobactin synthase, and pilL gene. Our findings demonstrate that beach sand-borne bacteria are reservoirs of virulence and antibiotic resistance genes. Contamination of beach sands with heavy metals selects for both heavy metal resistance and antibiotic resistance in beach sand bacterial communities. Children and immunocompromised people engaging in recreational activities on beaches may be exposed to higher risk of infection.

Microplastics on beaches along the eastern Gulf of Thailand - A preliminary study

Several studies have shown the ubiquitousness of microplastics across ecosystems worldwide including significant amounts in beach sand. In Thailand, however, there is a lack of studies about the microplastic pollution of beaches. This study aimed to quantify microplastics at the high-tide line of 21 beaches along the eastern Gulf of Thailand. Observed amounts ranged from 420 to >200,000 counts/kg. Anthropogenic and environmental factors affect distribution and amount of microplastics. Tide-dominated beaches and beach sections protected by beachrocks exhibit higher microplastic amounts due to lesser hydrodynamics. While human activities have a visible impact, in some cases environmental factors seem to predominate. Despite effective protection efforts led by the government and NGOs, our study shows that the substantial microplastic pollution of beach sand requires a proper management system with appropriate laws and regulations, and a public awareness campaign to reduce effects of microplastics on organisms and their ecosystems.

Spatial and temporal distribution of E. coli contamination on three inland lake and recreational beach systems in the upper Midwestern United States

Swimming advisories are commonly posted at public beaches across the United States every year. In Iowa, weekly monitoring of public swimming areas at state and county beaches have resulted in the impairment of numerous lakes for fecal indicator bacteria (FIB) contamination, as detected by E. coli. An extensive study was established to assess the relationships between E. coli contamination of nearshore beach water environments, open lake conditions and beach sands in three recreational beach/lake systems currently impaired for FIB contamination across Iowa. A transect/grab sample based sampling design was implemented across the systems with collections spanning from April through October of 2015 and 2016. Collections of E. coli along water transects identified strong near to far shore gradients of decreasing concentrations in all systems. Results indicate that concentrations of E. coli observed in swimming waters consistently disassociate with concentrations in the broader lake environment. Swimming water E. coli concentrations correlated with elevated beach sand E. coli, samples collected from beach sands uncovered concentrations up to 86,500 times higher than adjacent swimming waters. Results from this study indicate that foreshore beach sands and other beach proximate FIB sources serve as the major contributing source for swimming zone advisories. The current methodology used by state and federal officials includes impairing entire lake waterbodies for FIB contamination of the swimming area. These impairment listings do not accurately reflect the condition(s) of the larger lake environment outside the swimming area and fail to account for beach proximate conditions in the assessment process. Further, this approach provides potentially misleading information to the public and may undermine implementation strategies deployed by resource managers aimed at addressing FIB contamination at recreational swimming areas. Views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the Iowa Department of Natural Resources.

Biomonitoring of the environmental indicator and pathogenic microorganisms assortment in foremost pilgrimage beaches of the Bay of Bengal, Southeast coast, India

The present study is aimed to monitoring the ecological indicator and pathogenic microorganism diversity in pilgrimage places beach sand on the Bay of Bengal coast. The samples were collected from three locations and four different sites, and were analyzed by following standard methods. The results clearly indicates, ritual activities were highly contaminated in the beach sand qualities, and exceeded with the standard permissible limit of WHO, USEPA, EU, CPCB beach sand recreational and other contacts activities including pH (11%), TBC (100%), TCB (97%), FCB (88%), TEB (75%), E. coli (75%), disease-causing possible level of Klebsiella (84%), Shigella (75%), Salmonella (63%) and Vibrio (56%). The statistical tools were applied to find the strong evidence. The current study pointed out the major effects on the diffusion of potentially pathogenic microorganisms along the shoreline provided useful information for the setup of measures for public health protection in the Bay of Bengal coast.

Distribution and characterization of microplastics in beach sand from three different Indian coastal environments

The occurrence of microplastic particles were evaluated on beaches along the Indian coast from three different locations Girgaon Mumbai (Arabian sea coast), Tuticorin, and Dhanushkodi (Bay of Bengal coast). Density separation method was adopted for isolation of microplastics from sand. Isolated microplastics were characterized using three different analytical techniques e.g. fluorescence microscopy (after staining with Nile Red), FTIR and SEM-EDS techniques. Microplastic concentrations in beach sands were from 45 ± 12 # MP kg^-1 to 220 ± 50 # MP kg^-1 of dry sand. The order of abundance of plastic type was polyethylene (43%) > polyethylene terephthalate (17.3%) ≈ polystyrene (17%) > polypropylene (12.3%) > Others (11%) > polyvinylchloride (1.33%), and very similar profile was observed for all monitored locations. SEM images show microplastics surfaces with characteristic cracks, suggests their polymer aging, mechanical and oxidative weathering, which was found highest for the microplastics collected from Mumbai.

Effects of bacterial pollution caused by a strong typhoon event and the restoration of a recreational beach: Transitions of fecal bacterial counts and bacterial flora in beach sand

To determine the effects of bacteria pollution associated with a strong typhoon event and to assess the restoration of the normal bacterial flora, we used conventional filtration methods and nextgeneration sequencing of 16S rRNA genes to analyze the transition of fecal and total bacterial counts in water and core sand samples collected from a recreational beach. Immediately after the typhoon event, Escherichia coli counts increased to 82 CFU/100 g in the surface beach sand. E. coli was detected through the surface to sand 85-cm deep at the land side point (10-m land side from the high-water line). However, E. coli disappeared within a month from the land side point. The composition of the bacterial flora in the beach sand at the land point was directly influenced by the typhoon event. Pseudomonas was the most prevalent genus throughout the sand layers (0-102-cm deep) during the typhoon event. After 3 months, the population of Pseudomonas significantly decreased, and the predominant genus in the surface layer was Kaistobacter, although Pseudomonas was the major genus in the 17- to 85-cm layer. When the beach conditions stabilized, the number of pollutant Pseudomonas among the 10 most abundant genera decreased to lower than the limit of detection. The bacterial population of the sand was subsequently restored to the most populous pre-event orders at the land point. A land-side beach, where users directly contact the sand, was significantly affected by bacterial pollution caused by a strong typhoon event. We show here that the normal bacterial flora of the surface sand was restored within 1 month.

A new approach in separating microplastics from environmental samples based on their electrostatic behavior

Numerous studies on microplastics (MPs; Ø < 5 mm) in the aquatic environment have been published, but knowledge about the occurrence and ecological risks of MPs is limited. This is in part because current data on the distribution of MPs are comparable only to a limited extent, due to the many different methods of investigation. In addition, sample preparation is often difficult such that standard procedures are lacking. The aim of this work was to simplify the preparation of different kinds of MP samples. Our method makes use of the electrostatic behavior of plastic particles to facilitate their separation from sample matter, with up to 99% of the original sample mass removed without any loss of MPs. To determine the efficacy of this approach, four different materials (quartz sand, freshwater suspended particulate matter, freshwater sediment, and beach sand) were spiked with MPs (size: 0.063-5 mm from the seven most common types of plastics, one bioplastic type, polyethylene fibers, and tire wear. A modified electrostatic metal/plastic separator was used to reduce the sample mass and concentrate the plastics based on their physical separation. The recovery achieved with this method was as high as nearly 100% for each type of material. The method was then tested on plastic particles of different shapes and types isolated from the Rhine River. These were successfully electroseparated from the four materials, which demonstrated the utility of this method. Its advantages include the simplified handling and preparation of different field samples as well as a much shorter processing time, because after the last separation step there is hardly any biological material remaining in the sample fraction.

Isolation, identification, and pathological effects of beach sand bacterial extract on human skin keratinocytes in vitro

Background

Beaches are recreational spots for people. However, beach sand contains harmful microbes that affect human health, and there are no established methods for either sampling and identifying beach-borne pathogens or managing the quality of beach sand.

Method

This study was conducted with the aim of improving human safety at beaches and augmenting the quality of the beach experience. Beach sand was used as a resource to isolate bacteria due to its distinctive features and the biodiversity of the beach sand biota. A selected bacterial isolate termed FSRS was identified as Pseudomonas stutzeri using 16S rRNA sequencing and phylogenetic analysis, and the sequence was deposited in the NCBI GenBank database under the accession number MF599548. The isolated P. stutzeri bacterium was cultured in Luria-Bertani growth medium, and a crude extract was prepared using ethyl acetate to examine the potential pathogenic effect of P. stutzeri on human skin. A human skin keratinocyte cell line (HaCaT) was used to assess cell adhesion, cell viability, and cell proliferation using a morphological analysis and a WST-1 assay.

Result

The crude P. stutzeri extract inhibited cell adhesion and decreased cell viability in HaCaT cells. We concluded that the crude extract of P. stutzeri FSRS had a strong pathological effect on human skin cells.

Discussion

Beach visitors frequently get skin infections, but the exact cause of the infections is yet to be determined. The beach sand bacterium P. stutzeri may, therefore, be responsible for some of the dermatological problems experienced by people visiting the beach.

Elevated concentrations of naturally occurring radionuclides in heavy mineral-rich beach sands of Langkawi Island, Malaysia

Study is made of the radioactivity in the beach sands of Langkawi island, a well-known tourist destination. Investigation is made of the relative presence of the naturally occurring radionuclide ⁴⁰K and the natural-series indicator radionuclides ²²⁶Ra and ²³²Th, the gamma radiation exposure also being estimated. Sample quantities of black and white sand were collected for gamma ray spectrometry, yielding activity concentration in black sands of ²²⁶Ra, ²³²Th and ⁴⁰K from 451±9 to 2411±65Bqkg^-1 (mean of 1478Bqkg^-1); 232±4 to 1272±35Bqkg^-1 (mean of 718Bqkg^-1) and 61±6 to 136±7Bqkg^-1 (mean of 103Bqkg^-1) respectively. Conversely, in white sands the respective values for ²²⁶Ra and ²³²Th were appreciably lower, at 8.3±0.5 to 13.7±1.4Bqkg^-1 (mean of 9.8Bqkg^-1) and 4.5±0.7 to 9.4±1.0Bqkg^-1 (mean of 5.9Bqkg^-1); ⁴⁰K activities differed insubstantially from that in black sands, at 85±4 to 133±7Bqkg^-1 with a mean of 102Bqkg^-1. The mean activity concentrations of ²²⁶Ra and ²³²Th in black sands are comparable with that of high background areas elsewhere in the world. The heavy minerals content gives rise to elevated ²²⁶Ra and ²³²Th activity concentrations in all of black sand samples. Evaluation of the various radiological risk parameters points to values which in some cases could be in excess of recommendations providing for safe living and working. Statistical analysis examines correlations between the origins of the radionuclides, also identifying and classifying the radiological parameters. Present results may help to form an interest in rare-earth resources for the electronics industry, power generation and the viability of nuclear fuels cycle resources.

Next-generation sequencing and culture-based techniques offer complementary insights into fungi and prokaryotes in beach sands

A next-generation sequencing (NGS) approach, in conjunction with culture-based methods, was used to examine fungal and prokaryotic communities for the presence of potential pathogens in beach sands throughout Portugal. Culture-based fungal enumeration revealed low and variable concentrations of the species targeted (yeasts and dermatophytes), which were underrepresented in the community characterized by NGS targeting the ITS1 region. Conversely, NGS indicated that the potentially pathogenic species Purpureocillium liliacinum comprised nearly the entire fungal community. Culturable fecal indicator bacterial concentrations were low throughout the study and unrelated to communities characterized by NGS. Notably, the prokaryotic communities characterized revealed a considerable abundance of archaea. Results highlight differences in communities between methods in beach sand monitoring but indicate the techniques offer complementary insights. Thus, there is a need to leverage culture-based methods with NGS methods, using a toolbox approach, to determine appropriate targets and metrics for beach sand monitoring to adequately protect public health.

Assessment of natural radioactivity and gamma-ray dose in monazite rich black Sand Beach of Penang Island, Malaysia

Activity concentrations of primordial radionuclides in sand samples collected from the coastal beaches surrounding Penang Island have been measured using conventional γ-ray spectrometry, while in-situ γ-ray doses have been measured through use of a portable radiation survey meter. The mean activity concentrations for ²²⁶Ra, ²³²Th and ⁴⁰K at different locations were found to be less than the world average values, while the Miami Bay values for ²²⁶Ra and ²³²Th were found to be greater, at 1023±47 and 2086±96Bqkg^{̶ 1} respectively. The main contributor to radionuclide enrichment in Miami Bay is the presence of monazite-rich black sands. The measured data were compared against literature values and also recommended limits set by the relevant international bodies. With the exception of Miami Bay, considered an elevated background radiation area that would benefit from regular monitoring, Penang island beach sands typically pose no significant radiological risk to the local populace and tourists visiting the leisure beaches.

Shotgun metagenomic sequencing reveals freshwater beach sands as reservoir of bacterial pathogens

Recreational waters and adjacent beach sands harbor complex microbial communities which may contain human pathogens that cannot be detected by conventional methods. Here, we investigate the diversity of bacterial populations inhabiting four freshwater beaches of the Great Lakes region using shotgun metagenomic sequencing approach. Our analysis suggests that average taxonomic richness and alpha diversity are significantly higher (P < 0.001) in beach sands compared to the corresponding water environments. Compared to the water environments, beach sands harbored taxa from a more diverse range of phyla, including a higher proportion of sequences from unclassified phyla. Unique phyla were also identified in sand which included species from Aquificae, Candidatus Microgenomates, Latescibacteria, and Candidatus Aminicenantes. Sequences originating from pathogens were detected in both sand and water, with some pathogens enriched in both environments. Both lakes exhibited similar community composition suggesting that geographic location did not appear to have any major impact on bacterial diversity. These findings reveal the diversity of bacterial communities of freshwater beaches and highlight the importance of monitoring pathogens in recreational beaches, especially in the sand environment of these beaches.

Radiological maps in beach sands along some coastal regions of Turkey

In the present research, the gamma-emitting radionuclides in beach sands along the coastal regions of the Ordu, Giresun and Trabzon provinces, Turkey have been determined. The natural and anthropogenic radionuclide concentrations of the samples have been measured employing a germanium (HPGe) detector with high resolution and purity. The activity for ²³⁸U, ²³²Th, ⁴⁰K and ¹³⁷Cs of the samples were found to vary in the range from below detection limit (BDL) to 65Bq·kg^-1, from BDL to 28Bq·kg^-1, from 9 to 1936Bq·kg^-1 and from BDL to 22Bq·kg^-1, respectively. The activity concentrations were compared with those in the literature. The associated radiological hazard indices were estimated, and were compared to the internationally recommended values. The radiological map of beach sand in the surveyed area was imaged. The data presented in the study are crucial since they constitute a baseline for the radiological mapping of the region in the future.

Assessment of natural radioactivity and (137)Cs in some coastal areas of the Saudi Arabian gulf

The levels of natural radioactivity have been investigated in some Saudi Arabian Gulf coastal areas. Sampling sites were chosen according to the presence of nearby non-nuclear industrial activities such as, the two main water desalination plants in Al Khobar and Al Jubail, and Maaden phosphate complex in Ras Al Khair, to ensure that effluents discharges into the Arabian Gulf didn't enhance radioactivity in seawater and shore sediments. Seawater samples were analyzed for radium isotopes (Ra-226 & Ra-228) and measured by gamma spectrometry using high purity germanium detector, after radiochemical separation of the isotopes by co-precipitation with MnO2. Shore sediment samples were analyzed for (226)Ra, (228)Ra ((232)Th), (4)°K and (137)Cs using gamma sepectrometry. A small variation was observed in the activity concentrations of the investigated radioisotopes, and the activity levels were comparable to those reported in literature. Quality assurance and methods validation were established through the efficiency calibration of the detectors, the estimation of uncertainties, the use of blanks, the analysis of standard reference materials and the intercomparison and proficiency tests. Radiological hazards were assessed, and the annual effective dose had an average value of 0.02 mSv. On the basis of the current results, we may conclude that any radiological hazards to the public visiting these shores are not expected.

Comparison of the occurrence and survival of fecal indicator bacteria in recreational sand between urban beach, playground and sandbox settings in Toronto, Ontario

While beach sands are increasingly being studied as a reservoir of fecal indicator bacteria (FIB), less is known about the occurrence of FIB in other recreational sands (i.e., sandboxes and playgrounds). In this study, different culture-based FIB enumeration techniques were compared and microbial source tracking assays were conducted on recreational sand samples from beaches, playgrounds and sandboxes around Toronto, ON. FIB were detected in every sand sample (n=104) with concentrations not changing significantly over the five month sampling period. Concentrations of FIB and a gull-specific DNA marker were significantly higher in foreshore beach sands, and indicated these were a more significant reservoir of FIB contamination than sandbox or playground sands. Human- and dog-specific contamination markers were not detected. All culture-based FIB enumeration techniques were consistent in identifying the elevated FIB concentrations associated with foreshore beach sands. However, significant differences between differential agar media, IDEXX and Aquagenx Compartment Bag Test were observed, with DC media and Enterolert being the most sensitive methods to detect Escherichia coli and enterococci, respectively. To better understand the elevated occurrence of E. coli in foreshore sands, microcosm survival experiments were conducted at two different temperatures (15 °C and 28 °C) using non-sterile saturated foreshore beach sands collected from two urban freshwater beaches with different sand type (fine grain and sand-cobble). Microcosms were inoculated with a mixture of eight sand-derived E. coli strains and sampled over a 28-day period. E. coli levels were found to decline in all microcosms, although survival was significantly greater in the finer sand and at the cooler temperature (15 °C). These results indicate that FIB can be widespread in any type of recreational sand and, while E. coli can survive for many weeks, it is most likely to accumulate in cooler fine-grain sand as occurs below the foreshore sand surface.

Assessment of Ni, Cu, Zn and Pb levels in beach and dune sands from Havana resorts, Cuba

Concentrations of nickel (Ni), copper (Cu), zinc (Zn) and lead (Pb) in beach and dune sands from thirteen Havana (Cuba) resorts were estimated by X-ray fluorescence analysis. Determined mean metal contents (in mg·kg(-1)) in beach sand samples were 28±12 for Ni, 35±12 for Cu, 31±11 for Zn and 6.0±1.8 for Pb, while for dune sands were 30±15, 38±22, 37±15 and 6.8±2.9, respectively. Metal-to-iron normalization shows moderately severe and severe enrichment by Cu. The comparison with sediment quality guidelines shows that dune sands from various resorts must be considered as heavily polluted by Cu and Ni. Almost in every resort, the Ni and Cu contents exceed their corresponding TEL values and, in some resorts, the Ni PEL value. The comparison with a Havana topsoil study indicates the possible Ni and Cu natural origin.

Water quality, weather and environmental factors associated with fecal indicator organism density in beach sand at two recreational marine beaches

Recent studies showing an association between fecal indicator organisms (FIOs) in sand and gastrointestinal (GI) illness among beachgoers with sand contact have important public health implications because of the large numbers of people who recreate at beaches and engage in sand contact activities. Yet, factors that influence fecal pollution in beach sand remain unclear. During the 2007 National Epidemiological and Environmental Assessment of Recreational (NEEAR) Water Study, sand samples were collected at three locations (60 m apart) on weekend days (Sat, Sun) and holidays between June and September at two marine beaches - Fairhope Beach, AL and Goddard Beach, RI - with nearby publicly-owned treatment works (POTWs) outfalls. F(+) coliphage, enterococci, Bacteroidales, fecal Bacteroides spp., and Clostridium spp. were measured in sand using culture and qPCR-based calibrator-cell equivalent methods. Water samples were also collected on the same days, times and transects as the 144 sand samples and were assayed using the same FIO measurements. Weather and environmental data were collected at the time of sample collection. Mean FIO concentrations in sand varied over time, but not space. Enterococci CFU and CCE densities in sand were not correlated, although other FIOs in sand were. The strongest correlation between FIO density in sand and water was fecal Bacteroides CCE, followed by enterococci CFU, Clostridium spp. CCE, and Bacteroidales CCE. Overall, the factors associated with FIO concentrations in sand were related to the sand-water interface (i.e., sand-wetting) and included daily average densities of FIOs in water, rainfall, and wave height. Targeted monitoring that focuses on daily trends of sand FIO variability, combined with information about specific water quality, weather, and environmental factors may inform beach monitoring and management decisions to reduce microbial burdens in beach sand. The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency.

Routine screening of harmful microorganisms in beach sands: implications to public health

Beaches worldwide provide recreational opportunities to hundreds of millions of people and serve as important components of coastal economies. Beach water is often monitored for microbiological quality to detect the presence of indicators of human sewage contamination so as to prevent public health outbreaks associated with water contact. However, growing evidence suggests that beach sand can harbor microbes harmful to human health, often in concentrations greater than the beach water. Currently, there are no standards for monitoring, sampling, analyzing, or managing beach sand quality. In addition to indicator microbes, growing evidence has identified pathogenic bacteria, viruses, and fungi in a variety of beach sands worldwide. The public health threat associated with these populations through direct and indirect contact is unknown because so little research has been conducted relating to health outcomes associated with sand quality. In this manuscript, we present the consensus findings of a workshop of experts convened in Lisbon, Portugal to discuss the current state of knowledge on beach sand microbiological quality and to develop suggestions for standardizing the evaluation of sand at coastal beaches. The expert group at the "Microareias 2012" workshop recommends that 1) beach sand should be screened for a variety of pathogens harmful to human health, and sand monitoring should then be initiated alongside regular water monitoring; 2) sampling and analysis protocols should be standardized to allow proper comparisons among beach locations; and 3) further studies are needed to estimate human health risk with exposure to contaminated beach sand. Much of the manuscript is focused on research specific to Portugal, but similar results have been found elsewhere, and the findings have worldwide implications.

Microbial release from seeded beach sediments during wave conditions

Beach sands can sustain indigenous and introduced populations of enterococci. The objective of this study was to evaluate wave action in promoting the release of introduced bacteria. To accomplish this objective this study developed a method to assess attachment and identified conditions under which introduced bacteria are integrated into the sand. A new "shearing assay" showed that attachment of the introduced spike mimicked that of the natural sand when the spike was allowed to integrate into the sand for 24h at room temperature at a sand moisture content of 20%. Experiments in a wave flume showed that waves were capable of releasing about 60% of the total bacteria added. This suggests that for the range of wave conditions evaluated (height: 1.9-10.5 cm, period:1-2.7s), waves were incapable of releasing all of the bacteria. Further study is needed to evaluate bacteria attachment mechanisms.

Effects of full-scale beach renovation on fecal indicator levels in shoreline sand and water

Recolonization of enterococci, at a non-point source beach known to contain high background levels of bacteria, was studied after a full-scale beach renovation project. The renovation involved importation of new exogenous sand, in addition to infrastructure improvements. The study's objectives were to document changes in sand and water quality and to evaluate the relative contribution of different renovation activities towards these changes. These objectives were addressed: by measuring enterococci levels in the sand and fecal indicator bacteria levels (enterococci and fecal coliform) in the water, by documenting sediment characteristics (mineralogy and biofilm levels), and by estimating changes in observable enterococci loads. Analysis of enterococci levels on surface sand and within sediment depth cores were significantly higher prior to beach renovation (6.3-72 CFU/g for each sampling day) when compared to levels during and after beach renovation (0.8-12 CFU/g) (P < 0.01). During the renovation process, sand enterococci levels were frequently below detection limits (<0.1 CFU/g). For water, exceedances in the regulatory thresholds that would trigger a beach advisory decreased by 40% for enterococci and by 90% for fecal coliform. Factors that did not change significantly between pre- and post- renovation included the enterococci loads from animals (approx. 3 × 10(11) CFU per month). Factors that were observed to change between pre- and post- renovation activities included: the composition of the beach sand (64% versus 98% quartz, and a significant decrease in biofilm levels) and loads from direct stormwater inputs (reduction of 3 × 10(11) CFU per month). Overall, this study supports that beach renovation activities contributed to improved sand and water quality resulting in a 50% decrease of observable enterococci loads due to upgrades to the stormwater infrastructure. Of interest was that the change in the sand mineralogy also coincided with changes in biofilm levels. More work is needed to evaluate the relationships between beach sand mineralogy, biofilm characteristics, and the retention of fecal indicator bacteria in sand.