Microplastic pollution on sandy beaches of Puerto Rico.

Caribbean islands, including Puerto Rico, are biodiversity hotspots threatened by microplastics (<5 mm). Little is known about the extent of microplastic pollution in coastal sandy beaches of Puerto Rico. Sand from six northern beaches was collected in the high tide line to determine microplastic abundance (0.3-4.75 mm). Península La Esperanza, the most polluted beach, exhibited higher average abundance (17 items/kg dw) and diversity. High urbanization, industrial/port activities, and riverine input are likely sources of plastic debris on this beach. The other beaches showed lower and similar average abundance (3 to 7 items/kg dw) despite having distinct potential point and non-point sources. Overall, fibers (40%), fragments (28%) and foams (27%) predominated (n = 102 particles). Results showed comparable levels to other world beaches, some classified as highly contaminated, but only when transforming units to items/m2. Preliminary ATR-FTIR analysis identified mainly polyethylene. It is imperative to have plastics source reduction through waste management.

Passive Sampling of Persistent Organic Pollutants in Four Coastal Aquatic Systems of Puerto Rico: A Pilot Study.

Little is known about the presence and effects of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in Puerto Rico's waters. Four coastal aquatic systems were investigated using low-density polyethylene passive sampling for PCBs and OCPs in water and its overlying air. The highest total freely dissolved and gaseous concentrations of PCBs were found in Guánica Bay, with 4000 pg/L and 270 pg/m3, respectively. Five OCPs were detected, mainly in water, with greatest concentrations (pg/L) in Guánica Bay: α-HCH (7400), p,p'-DDE (390), aldrin (2000), dieldrin (420), and endrin (77). The compound α-HCH was also measured at elevated water concentrations in Condado Lagoon (5700 pg/L) and Laguna Grande (2900 pg/L). Jobos Bay did not show values of concern for these persistence organic pollutants. Levels of PCBs and OCPs in water, particularly in Guánica Bay, exceeded USEPA ambient water quality criteria values representing a human health risk regarding consumption of aquatic organisms.

Assessing arsenic exposure from consumption of seafood from Vieques-Puerto Rico: a pilot biomonitoring study using different biomarkers.

The various toxic effects associated with inorganic arsenic (iAs) warrants that exposure sources be identified. This pilot study evaluated if greater seafood consumption from Vieques-Puerto Rico is associated with increased exposure to iAs. Nail, hair, and urine samples were used as biomarkers of iAs exposure in adult women and men from Vieques classified as high (n = 31) and low (n = 21) seafood consumers, who reported eating fish and/or shellfish ≥1 time per week and once per month or less, respectively. The sum of urinary iAs (As III + As V), monomethylarsonic acid (MA[V]), and dimethylarsinic acid (DMA[V]), denoted as SumAs, fluctuated from 3.3 µg/g Cr (1.2 µg/L) to 42.7 µg/g Cr (42 µg/L) (n = 52). Levels of As in nail samples (n = 49) varied from 0.04 to 0.82 µg/g dry weight (dw), whereas in hair (n = 49) As was only detected in 49 % of the samples with a maximum value of 0.95 µg/g dw. None of the biomarkers of exposure to As exceeded exposure reference values for urine (50 µg/g Cr or 50 µg/L), nails (1 µg/g), or hair (1 µg/g). However, median (10.0 µg/g Cr; 10.6 µg/L) and 95th percentile (31.9 µg/g Cr; 40.4 µg/L) of urinary SumAs were higher in Vieques samples than in the those from the general population of other countries. Among the three biomarkers of exposure, nail samples reflected better the exposure to iAs from seafood consumption with significantly higher average As concentrations in high (0.24 µg/g) than low (0.12 µg/g) seafood consumers. Multivariate results for As in nail samples (R(2) = 0.55, p < 0.0001) showed a positive association with fish consumption, particularly for men, with levels increasing with years of residency in Vieques.

A pilot study determining hair arsenic and lead levels in residents of a community established on a former landfill in Puerto Rico.

Arsenic (As) and lead (Pb) were determined in hair of 12 adult women and 27 children living in a soil-metal contaminated community in Puerto Rico. Average concentrations in residential soils ranged from 24 to 109 µg/g for As and from 42 to 1,585 µg/g for Pb. For hair-As, about 75% of the samples were below 0.08 µg/g. Hair-Pb presented levels of health concern, with 10% of the samples above a reference value of 5 µg/g, indicating significant exposure to Pb. Multivariate analyses revealed that children's Pb hair levels were predicted by age and sex, while consumption of home-grown animals influenced the association with soil-Pb.

Metal levels in fish captured in Puerto Rico and estimation of risk from fish consumption.

Exposure to metals through fish consumption may represent a health risk, especially for high-fish-consumption populations such as fishing communities in the Jobos Bay and La Parguera areas in Puerto Rico. This study determined levels of As, Cd, Cu, Pb, Hg, Se, and Zn in muscle tissues of fish from the Jobos Bay and La Parguera (reference site) areas and estimated the health risk posed by fish ingestion to local fishermen and their children. Fish collected included S. cavalla ("sierra"; n = 14), M. undulatus ("roncón"; n = 21), L. synagris ("arrayado"; n = 18), and L. analis ("sama"; n = 11) in the Jobos Bay area and S. regalis (sierra; n = 10) and L. synagris (arrayado; n = 8) in La Parguera. Only As and Hg were detected at levels of human health concern. Average As and Hg levels (µg/g, wet wt) in the four species of Jobos Bay were 0.74 and 0.10 for roncón, 0.83 and 0.09 for sama, 1.00 and 0.26 for sierra, and 2.49 and 0.15 for arrayado, respectively. In La Parguera, average As and Hg levels (µg/g, wet wt) were 0.61 and 0.12 for sierra and 1.27 and 0.20 for arrayado, respectively. At both sites, the species with the highest As levels was arrayado, while for Hg, sierra obtained the highest concentrations. A risk estimation using U.S. Environmental Protection Agency standard exposure factors, and assuming that 10% of total As is the inorganic form and 100% of the total Hg is methyl Hg, predicted adverse health effects (cancer and noncancer) from fish consumption, being higher for children than for adults. However, speciation of As in fish muscle is recommended for better risk estimates. Sierra fish from Jobos Bay triggered the most restricted consumption advisories for Hg noncancer effects, where a child should not consume >1 fish meal (0.1135 kg)/month and adults should not have >3 fish meals (0.227 kg)/month. Fish consumption advisories, particularly for Hg, should be established by the local government to protect the health of susceptible populations such as children and pregnant or childbearing-age women.

Trace metals, PAHs, and PCBs in sediments from the Jobos Bay area in Puerto Rico.

This study provides baseline information on the extent of contamination in sediments of the Jobos Bay estuary and surrounding areas in Puerto Rico. Sediments from Jobos Bay area (n=14) had higher overall average concentrations than those from La Parguera area (n=5, used as reference site), in microg/g dw, for As (17 vs 9), Cu (29 vs 14), Pb (11 vs 4), and Zn (64 vs 28); and in %, for Fe (2.6 vs 0.6). Sediments (n=8) screened for PAHs and PCBs exhibited total concentrations (ng/g dw) that ranged from 40.4 to 1912, and from not detected to 11.21, respectively. The quality of sediments of Jobos Bay could be classified as low to moderate pollution. The proximity to anthropogenic sources of contamination warrants a monitoring program for inorganic and organic pollutants in Jobos Bay area for an effective coastal management program of this tropical ecosystem.

Concentrations of Ni and V, other heavy metals, arsenic, elemental and organic carbon in atmospheric fine particles (PM2.5) from Puerto Rico.

Fine atmospheric particulate PM2.5 (particles with diameters of < 2.5 microm) were sampled in an urban industrialized area--Guaynabo, Puerto Rico (Figure 1)--and in a reference less polluted site Fajardo, Puerto Rico--and analyzed for trace metals, and inorganic and organic elemental carbon. PM2.5 samples were collected from November 2000 to September 2001 using an Andersen Instruments RAAS2.5-400 for periods of 72 h. Metals analyzed were arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), vanadium (V) and zinc (Zn) by atomic absorption. Levels of elemental and organic carbon (EC/OC) were also determined. All metals analyzed, except for Fe, were significantly higher in PM2.5 from Guaynabo when compared to Fajardo. Average levels of PM2.5 in Guaynabo were 11.6 versus 8.5 microg/m3 in Fajardo. Average levels of EC were 1.5 and <0.14 microg/m3; and OC levels were 2.2 and < 1 microg/m3 for Guaynabo and Fajardo, respectively. Levels of Ni (17 ng/m3) and V (40 ng/m3) determined in PM2.5 from the Guaynabo area were high when compared to other cities, and these metals could be responsible for respiratory problems reported in the area. Multivariate analyses showed strong relationships in Guaynabo between Ni and V, PM2.5 and Fe and As and Cu and Pb. In Fajardo, the strongest associations were obtained between PM2.5 and Fe, Cd and V and Ni and Pb and Cu, these last three elements exhibiting an inverse relationship.

Effect of three extraction techniques on submitochondrial particle and Microtox bioassays for airborne particulate matter.

The effect that three extraction techniques (e.g., Soxhlet, ultrasound and microwave-assisted extraction) have on the toxicity, as measured by submitochondrial particle (SMP) and Microtox assays, of organic extracts was compared from three sources of airborne particulate matter (APM). The extraction technique influenced the toxicity response of APM extracts and it was dependent on the bioassay method, and APM sample source. APM extracts from microwave-assisted extraction (MAE) were similar or more toxic than the conventional extraction techniques of Soxhlet and ultrasound, thus, providing an alternate extraction method. The microwave extraction technique has the advantage of using less solvent volume, less extraction time, and the capacity to simultaneously extract twelve samples. The ordering of APM toxicity was generally urban dust > diesel dust > PM10 (particles with diameter < 10 microm), thus, reflecting different chemical composition of the samples. This study is the first to report the suitability of two standard in-vitro bioassays for the future toxicological characterization of APM collected from Puerto Rico, with the SMP generally showing better sensitivity to the well-known Microtox bioassay.

The association of lead-contaminated house dust and blood lead levels of children living on a former landfill in Puerto Rico.

Exposure to lead in children living on a former landfill in Vega Baja-Puerto Rico, a United States Environmental Protection Agency (USEPA) designated Superfund Site, is a major health concern. Direct contact with lead-contaminated soil is considered a major exposure source. However, there is a lack of information regarding the contribution of lead-contaminated house dust to children's blood lead concentrations. This study evaluated the relationship between lead contaminated-house dust and children's blood lead levels. Blood from 42 children, aged 6 years old or less, and dust from 29 houses were analyzed for lead, and face-to-face interviews were performed to gather information on potential risk factors for high blood lead levels. Blood lead levels ranged from 0.97 to 7.79 micrograms/dL. Lead values for floors fluctuated from 0.12 to 98.30 micrograms/ft2, with 17% of houses surpassing the USEPA standard of 40 micrograms/ft2. Multiple regression analysis showed that lead in window sills, toy chewing and soil eating habits were significant predictors of blood lead levels. Further investigations aimed at assessing the long-term effects of constant exposure to environmental lead in these children are warranted.