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Brazil has a coastline with large cities and a great flow of human activities, which can lead to contamination by microorganisms and parasites. Given this context, the objective of this study was to evaluate the parasitic and microbiological events in the sand of beaches in São Luís, Maranhão. Therefore, four samples were collected from three beaches, thus totaling 12 samples. Each area was divided into four distinct segments, two dry and two wet, and for each sample, sterile collectors were inserted into the sand at a depth of 20 centimeters. The samples were identified, placed in a Styrofoam box, and taken to the laboratory for analysis. The parasitological analysis was performed through spontaneous sedimentation and centrifugation, while the microbiological analysis used the COLItest® kit to determine total and thermotolerant coliforms (Escherichia coli). All the sand samples were positive (100%) for helminths and/or protozoa, and the most frequent helminth and protozoan were Trichuris trichiura (100%; n=12 ) and Giardia lamblia (83.3%; n=10), respectively. Microbiological analyses showed that 66.6% (8/12) were contaminated by total coliforms and 58.3% (7/12) by Escherichia coli. Collection point 3 of dry sand from São Marcos beach (Sm3S) showed the highest contamination by Escherichia coli (4.33x102 CFU/mL). The beaches on the seafront called Litorânea in São Luís are contaminated by parasites and fecal bacteria from animals or human sources on the beach. Thus, the probability of acquiring infections increases among individuals visiting these environments.

Whiley, H.; Austin, J.; da Silva, G.M., and Ross, K., 2018. Faecal indicator bacteria present in sand at South Port Beach, South Australia. Research has demonstrated that bacterial pathogens present in beach sand may be a risk to human health. The indicator species enterococci, total coliforms, and Escherichia coli were measured in beach sand collected from South Port Beach, South Australia, a popular recreational beach. Samples were collected from five distances from the low tide mark (low tide, 10 m, 20 m, 30 m, and 40 m), at three depths (surface, 10 cm down, and 30 cm down), and at five sampling times over a 3-month period. During this time there was a storm that resulted in significant movement of sand from the beach and high flow of the nearby river, and coincided with increased bacterial load. Within a week the bacterial load had returned to previously measured levels. In general, higher bacterial counts were at the surface level compared with 10 and 30 cm below the surface, and the lower counts were at the low tide mark, with increasing distance from the low tide resulting in increasing bacterial loads, and the highest load at the dune edge. This research provides information about the potential health risk of beach sand and a baseline for future studies exploring the microbial risks of Australian beach sand. [ABSTRACT FROM AUTHOR]

The impact of Shokarski stormwater canal on the bathing waters quality of Varna Bay located in the northern Bulgarian Black Sea was investigated during 2007-2014. A total of five monitoring stations were selected: three city beaches near the area of discharge of the stormwater canal and two nearby resorts beaches. The water quality was assessed following the requirements of the old EU Bathing Water Directive (BWD) 76/160/EEC and the new BWD 2006/7/EC. The resort beaches exhibited excellent water quality through the whole period. The situation at the city beaches was worst. The 'Officers Beach' situated exactly at the area of discharge of Shokarski stormwater canal exhibited concentrations of ammonium and nitrates significantly above the guide value in most of the cases, the lowest compliance with the total coliforms and faecal coliforms guide values and the highest concentrations of Escherichia coli and intestinal enterococci. [ABSTRACT FROM AUTHOR]

Several beaches within the Toronto region area of concern have persistent issues with fecal contamination, causing a beach beneficial use impairment (BUI). In this study, Escherichia coli, including ampicillin-resistant strains, were enumerated via culturable and quantitative polymerase chain reaction (qPCR) methods. Microbial source tracking (MST) markers (for general Bacteroidales, human, ruminant/cow, gull, and dog) were detected and enumerated via PCR and qPCR to identify sources of fecal contamination at Sunnyside Beach and in the Humber River. Human, cow, and dog markers had good host-specificity, while gull markers sometimes amplified a few other bird species. The ruminant endpoint PCR marker amplified a variety of other animal species rendering it less useful. Both human and gull fecal contamination were prevalent in the Humber River, while Sunnyside Beach was predominantly impacted by gull fecal contamination. Human sewage impacts were more prevalent in the lower Humber River, particularly in Black Creek. However, to reduce Sunnyside beach postings, reducing bird fecal contamination in the river and at the beach would be necessary. When there are high levels of E. coli throughout a beachshed, an MST toolbox approach can add value to discriminate source(s) of E. coli contamination and guide decisions relating to public health risk and remediation strategies. [ABSTRACT FROM AUTHOR]

This work has been carried out to monitor and decrease the natural radiation exposure at the Hantepe beach (Çanakkale, Turkey). A 0.25- to 0.30-m-thick layer of sand was scraped, removed and deposited in a safe place in order to decrease people's exposure to radiation and to relieve relevant radiophobia. The original mean value of dose rate on the beach was 1.38 μGy h−1 at the contact and 1.0 μGy h−1 at 1 m above the ground. After the scraping process, the mean value of dose rate decreased to 0.98 μGy h−1 at the contact and to 0.78 μGy h−1 at 1 m above the ground. One year later, these values decreased to 0.70 μGy h−1 at the contact and to 0.56 μGy h−1 at 1 m above the ground. The effective original dose rate of 1.2 mSv y−1 decreased to 0.95 mSv y−1 after the surface treatment and to 0.69 mSv y−1 one year later. [ABSTRACT FROM AUTHOR]

Gulls are often cited as important contributors of fecal contamination to surface waters, and some recreational beaches have used gull control measures to improve microbial water quality. In this study, gulls were chased from a Lake Michigan beach using specially trained dogs, and water quality improvements were quantified. Fecal indicator bacteria and potentially pathogenic bacteria were measured before and during gull control using culture methods and quantitative polymerase chain reaction (qPCR). Harassment by dogs was an effective method of gull control: average daily gull populations fell from 665 before to 17 during intervention; and a significant reduction in the density of a gull-associated marker was observed (p < 0.001). Enterococcus spp. and Escherichia coli densities were also significantly reduced during gull control (p < 0.001 and p = 0.012, respectively for culture methods; p = 0.012 and p = 0.034, respectively for qPCR). Linear regression results indicate that a 50% reduction in gulls was associated with a 38% and 29% decrease in Enterococcus spp. and E. coli densities, respectively. Potentially human pathogenic bacteria were detected on 64% of days prior to gull control and absent during gull intervention, a significant reduction (p = 0.005). This study demonstrates that gull removal can be a highly successful beach remedial action to improve microbial water quality. [ABSTRACT FROM AUTHOR]

Beach sediment and sand are recognized as nonpoint fecal indicator bacteria (FIB) sources capable of causing water quality and health risks for beach-goers. A comprehensive understanding of the key factors and mechanisms governing the migration and exchange of FIB between beach water column and sediment is desired to better predict FIB concentration variations and assess the associated risk. The transport and retention behavior of two model FIB Enterococcus faecalis (E. faecalis) and Escherichia coli (E. coli) was examined using packed-bed columns in both saturated and unsaturated porous media to evaluate FIB migration potentials at conditions simulating the coastal aquatic environment. Additionally, complementary cell characterization techniques were conducted to better understand the migration behaviors of both FIB strains observed in the column experiments. The mobility of the gram-positive species E. faecalis was much more sensitive to solution chemistry and column saturation level than that of the gram-negative species E. coli. Interaction energy calculations suggest that E. faecalis retention was largely governed by the combination of DLVO (Derjaguin-Landau-Verwey-Overbeek) and non-DLVO (most likely hydrophobic and/or polymer bridging) interactions in saturated porous media, while the combination of DLVO and steric interactions controlled the deposition of E. coli cells. The measured surface properties of the two FIB strains supported the distinct bacteria transport behaviors and the differences of the identified mechanisms for each strain. As a result, E. faecalis showed the least affinity to sand in freshwater and appeared to be irreversibly attached in primary energy minima at elevated salt conditions; whereas the retained E. coli cells were reversibly attached and mostly associated with the secondary energy minima at both freshwater and seawater conditions. In unsaturated porous media, E. faecalis cells seemed to prefer to attachment at air/water interface rather than sand surface, while E. coli showed a similar affinity to the two interfaces. It was proposed that the different surface characteristics of the two FIB strains resulted in the distinct transport and retention behavior in porous media. These results highlight the need for FIB management to consider variations in transport behavior between model FIB when assessing water quality and associated risks. [ABSTRACT FROM AUTHOR]