Biomedical waste generation at Ayurveda hospitals in South Asia: A mini review of the composition, quantities and characteristics.

Ayurveda hospitals generate biomedical wastes (BMW). However, details on composition, quantities and characteristics are very scarce, details which are important to formulate a proper waste management plan for subsequent implementation and continual improvement. Therefore, this article presents a mini review of the composition, quantities and characteristics of BMW generated from Ayurveda hospitals. Additionally, this article presents some best possible treatment and disposal procedures. Most of the information was gleaned from peer-reviewed journals, although some information was collected by the author and from grey literature available to the author; 70-99% (by wet weight) of the solid waste is non-hazardous; biodegradables contributing to 44-60% by wet weight due to more used Kizhi (medicinal bags for fomentation) and other medicinal/pharmaceutical wastes (excluding waste medicated oils, which is 12-15% of the liquid medicinal waste stream and are not readily biodegradable) largely derived from plants. The hazardous waste component includes infectious wastes, sharps, blood as pathological wastes (from Raktamoksha - bloodletting), heavy metal containing pharmaceutical wastes, chemical wastes and heavy metal rich wastes. Quantities of infectious wastes followed by sharps and blood form a major portion of hazardous wastes. Most of the infectious waste material contaminated with blood or other body fluids and sharps from Raktamoksha are very similar (appearance, moisture content and bulk density) to what is generated from hospitals practicing Western medicine. However, hospital-specific waste studies are required in future to better understand the sources, areas of generation, types, quantities and characteristics of BMW, and hence to formulate more accurate waste management plans.

A mini review of hazardous wastes generated by environmental analytical laboratories: a perspective from Sri Lanka as an economically developing country.

Attention given to environmental pollution caused by environmental analytical (EA) laboratories is very poor in Sri Lanka (an economically developing country). This article discusses EA laboratory effluents and hazardous solid wastes, current environmental management practices, and the legislative requirements in Sri Lanka. Effluent quantities generated are low (29.99-63.09 L/week), but characterized with variable pH, high chemical oxygen demand (COD), total suspended solids (TSS) and heavy metals, and very high ecotoxicity. Quantities of chemical-contaminated solid wastes is 80-100 kg/year (excluding outdated and rejected chemicals). Most laboratories dispose chemical-contaminated solid wastes mixed with non-hazardous recyclables using the services of local authorities and some laboratories (particularly in areas where there is no municipal solid waste collection), practice backyard dumping or open burning, while a few laboratories employ private parties to dispose or burn these wastes elsewhere. Only one laboratory is disposing chemical-contaminated solid wastes through co-processing. Appropriate waste management strategies (including some cleaner production concepts) are discussed in this paper for selected streams of hazardous wastes.

Fish diversity and assemblage in the Batticaloa lagoon, Sri Lanka.

The Batticaloa Lagoon (Sri Lanka's third-largest brackish waterbody) has suffered habitat degradation and water quality deterioration during the past 30 years due to various anthropogenic activities. Despite Sri Lanka having 40 lagoons, inventories on the lagoon ichthyofauna are rather meagre and data on fish diversity and assemblages are scarce. An assessment of fish diversity is essential to maintain the ecological stability and lagoon fisheries. This study examined the fish fauna of the Batticaloa lagoon considering the northern and southern regions of the lagoon and various depths through a 3-year survey (2017-2019) and documented the dominant and rare fish species. In addition, biodiversity measures, species assemblages and the role of environmental parameters on the distribution of fishes were documented. Various diversity indices (the Margalef richness index, the Shannon-Weiner diversity index, Pielou's evenness index, the dominance index, the taxonomic diversity index, the average taxonomic distinctness index and the total taxonomic distinctness index) were calculated. Analysis of similarities (ANOSIM) was used to examine the seasonal and regional differences in the fish assemblages. The survey showed the occurrence of 96 species belonging to 40 families and 11 orders. Ambassis gymnocephalus was the most abundant fish species (8.7% of the total number of fishes collected) followed by Etroplus suratensis (6.8%), Arius maculatus (6.1%), Gerres filamentosus (5.3%), Oreochromis niloticus (4.6%) and Gerres abbreviates (3.9%). Dasyatis uarnak (0.02%), Acanthurus gahhm (0.03%), Alectis ciliaris (0.04%) and Crossorhombus valderostratus (0.08%) were considered as rare species which constitute less than 0.1% of the total while D. uarnak was considered a doubletons species (represented twice in the whole sample of 16 stations). Two types of species assemblages, one in the northern region and one in the southern region, were evident in a dendrogram (Based on the samples were collected on each region dendrogram were plotted with respect to sites then finally dendrogram of one region pratly connected by other region) based on sample composition similarity estimated with a Bray-Curtis matrix and nonmetric multidimensional scaling plots. The Bray-Curtis dissimilarity was 59.03% between the two regions, indicating statistically significant differences in assemblages (ANOSIM R 0.801; P < 0.01). The northern region of the lagoon had a higher number of species, density, Margalef richness, Pielou's evenness, Shannon-Wiener diversity, taxonomic diversity, taxonomic distinctness and total taxonomic distinctness compared to the southern region. The northern region showed significantly higher levels of salinity and dissolved oxygen (DO) and the southern region higher temperature, turbidity, phosphates and nitrates. The best subset of biota and environmental variables [BEST(BIO-ENV)] test showed a significant relationship between fish assemblage and environmental parameters. Distance-based linear model analysis showed a significant relationship between fish assemblage and the environmental parameters salinity, temperature, pH and DO. The sequential test of this analysis showed the environmental parameters to explain about 74.9% (R2 ) of the total variation. The bioenvironmental model developed was found to be appropriate. Thirteen species were found to be influential as they explained the overall fish distribution pattern with a Spearman rank correlation of 0.951. Ten groups of coherent species were also identified in the study area. In stations having anthropogenic activities, the fish diversity was low. The fish fauna of the Batticaloa lagoon should be monitored periodically to protect the fishery resources here. An understanding of the role that environment plays in structuring the fish assemblage in the Batticaloa lagoon and locations with critical habitats will be of great importance in the conservation and management of fishery resources in this lagoon. However, as monitoring only the dominant species may fail to pick up on important impacts affecting the less common species, it should be done using diversity indices and rare fish species. Monitoring is imperative in view of the livelihood of the fishers this lagoon supports and the health of the local people, as fish is a healthy food. The fishery resources of this lagoon must be protected for posterity with appropriate management measures.

Are mangrove forests reliable sinks of heavy metals due to phytoremediation and other mechanisms? A Sri Lankan perspective.

We present a viewpoint regarding the prospects in Sri Lanka (a tropical island nation) to depend on mangroves in the remediation of heavy metal laden coastal environments. Sri Lanka has a rich array of lagoons and estuaries (total extent of 1580.17 km2) with ideal brackish water habitats to allow mangrove proliferation and for more restoration works. Furthermore, our estimates of Total Potential Ecological Risk (PER < 150) indicate that ecological risk from metallic contamination of coastal sediments is low, which means mangrove ecosystems would be ideal natural treatment systems for such low polluting environments (but as final cum tertiary treatment systems only). Mangroves are neither metal hyperaccumulators nor good phytoremediators (no ability to take up more than 5000 mg/kg dry weight of a given metal or exhibit a bioconcentration factor ≥ 1000), which means not very effective for high polluting environments.

Bio-transfer factors and temporal variation of heavy metals in different sexes of three species of edible brackish water fish.

This article discusses bioaccumulation and temporal variation of heavy metals in three edible lagoon fish species with references to gender. Cd and As were undetected in the three fish species (i.e., below the method detection limits of 1 µg Cd/kg wet weight and 2 µg As/kg wet weight) irrespective of the periods, and Cd was undetected in the water too (i.e., below the detection limit of 0.0003 mg/L). Except for Zn (which was mainly available as Zn2+ in the water), Pb was present largely as low labile metal-chloride complexes and As as HAsO42- as per Visual MINTEQ, version 3.1. Bio-transfer factors of Sn (which was also undetected in the water; below the detection limit of 0.05 mg/L), Hg, Pb, and Zn were <1 in both sexes, justifying that bioaccumulation was largely attributed to food rather than uptake from the water. Metal accumulation patterns differed drastically between the fish species. Arius maculatus (a carnivore) exhibited higher Zn, Hg, and Sn accumulations during the drier periods (June-September) compared with Mugil cephalus (a detritivore/herbivore) and Etroplus suratensis (an omnivore). Pb was detected only in A. maculatus (July-August) possibly due to biomagnification. Zn was present in higher levels in all species (irrespective of sex) compared with the other metals, but levels were below admissible limits. However, the relationship between temporal variation of Zn and gender in all species was insignificant. In M. cephalus, the temporal variation of Sn and Hg between the sexes was also insignificant. Female A. maculatus and E. suratensis showed higher Hg concentrations, while males showed higher Sn concentrations. Temporal variation patterns of Pb were unclear.

Spatial and temporal distribution of cyanobacteria in Batticaloa Lagoon.

The necessity to understand the relationship between cyanobacterial species abundance and water quality variations in coastal lagoons is crucial to develop strategies to prevent further cyanobacterial proliferation. This paper evaluates the relationship between water quality variations on the distribution of cyanobacteria during a 12-month period in Batticaloa Lagoon (Sri Lanka) using Redundancy analysis and Pearson correlations. Drastic variations in pH, temperature, salinity, dissolved oxygen (DO) and total phosphorus (TP) levels were reported, but not turbidity and NO3(-). This brackish waterbody is hypereutrophic (TP levels>0.1mg/L). The cyanobacterial community contained 13 genera and 22 species. NO3(-), TP and turbidity levels positively influenced cyanobacterial abundance during all seasons indicating that nutrient (largely phosphorus) and sediment entry control is highly crucial along with periodic monitoring of cyanobacterial growth.