The Environmental Protection Agency (EPA) provides access to information on a variety of topics related to the environment and strives to inform citizens of health risks. The EPA also has an extensive library network that consists of 26 libraries throughout the United States, which provide access to a plethora of information to EPA employees, scientists, and researchers. The EPA implemented a reorganization project to digitize their materials so they would be more accessible to a wider range of users, but this plan was drastically accelerated when the EPA was threatened with a budget cut. It chose to close and reduce the hours and services of some of their libraries. As a result, the agency was accused of denying users the “right to know” by making information unavailable, not providing an adequate strategic plan, and discarding vital materials. This case study explores the background of the digitization project, the practices implemented, and the critiques of the project.

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The Environmental Protection Agency

Habitat loss has pervasive and disruptive impacts on biodiversity in habitat remnants. The magnitude of the ecological impacts of habitat loss can be exacerbated by the spatial arrangement -- or fragmentation -- of remaining habitat. Fragmentation per se is a landscape-level phenomenon in which species that survive in habitat remnants are confronted with a modified environment of reduced area, increased isolation and novel ecological boundaries. The implications of this for individual organisms are many and varied, because species with differing life history strategies are differentially affected by habitat fragmentation. Here, we review the extensive literature on species responses to habitat fragmentation, and detail the numerous ways in which confounding factors have either masked the detection, or prevented the manifestation, of predicted fragmentation effects. Large numbers of empirical studies continue to document changes in species richness with decreasing habitat area, with positive, negative and no relationships regularly reported. The debate surrounding such widely contrasting results is beginning to be resolved by findings that the expected positive species-area relationship can be masked by matrix-derived spatial subsidies of resources to fragment-dwelling species and by the invasion of matrix-dwelling species into habitat edges. Significant advances have been made recently in our understanding of how species interactions are altered at habitat edges as a result of these changes. Interestingly, changes in biotic and abiotic parameters at edges also make ecological processes more variable than in habitat interiors. Individuals are more likely to encounter habitat edges in fragments with convoluted shapes, leading to increased turnover and variability in population size than in fragments that are compact in shape. Habitat isolation in both space and time disrupts species distribution patterns, with consequent effects on metapopulation dynamics and the genetic structure of fragment-dwelling populations. Again, the matrix habitat is a strong determinant of fragmentation effects within remnants because of its role in regulating dispersal and dispersal-related mortality, the provision of spatial subsidies and the potential mediation of edge-related microclimatic gradients. We show that confounding factors can mask many fragmentation effects. For instance, there are multiple ways in which species traits like trophic level, dispersal ability and degree of habitat specialisation influence species-level responses. The temporal scale of investigation may have a strong influence on the results of a study, with short-term crowding effects eventually giving way to long-term extinction debts. Moreover, many fragmentation effects like changes in genetic, morphological or behavioural traits of species require time to appear. By contrast, synergistic interactions of fragmentation with climate change, human-altered disturbance regimes, species interactions and other drivers of population decline may magnify the impacts of fragmentation. To conclude, we emphasise that anthropogenic fragmentation is a recent phenomenon in evolutionary time and suggest that the final, long-term impacts of habitat fragmentation may not yet have shown themselves.

Confounding factors in the detection of species responses to habitat fragmentation

Cryptosporidium spp. and cryptosporidiosis.

Climate Change 1995 is a scientific assessment that was generated by more than 1 000 contributors from over 50 nations. It was jointly co-ordinated through two international agencies; the World Meteorological Organization and the United Nations Environment Programme. The assessment was completed by the Intergovernmental Panel on Climate Change (IPCC) with a primary aim of reviewing the current state of knowledge concerning the impacts of climate change on physical and ecological systems, human health, and socioeconomic factors. The second aim was to review the available information on the technical and economic feasibility of the potential mitigation and adaptation strategies.

Climate Change 1995

https://apha.confex.com/apha/responses/129am/165.pdf

Effects of environmental change on emerging parasitic diseases.

Recent molecular characterizations of Cryptosporidium parasites make it possible to differentiate the human-pathogenic Cryptosporidium parasites from those that do not infect humans and to track the source of Cryptosporidium oocyst contamination in the environment. In this study, we used a small-subunit rRNA-based PCR-restriction fragment length polymorphism (RFLP) technique to detect and characterize Cryptosporidium oocysts in 55 samples of raw surface water collected from several areas in the United States and 49 samples of raw wastewater collected from Milwaukee, Wis. Cryptosporidium parasites were detected in 25 surface water samples and 12 raw wastewater samples. C. parvum human and bovine genotypes were the dominant Cryptosporidium parasites in the surface water samples from sites where there was potential contamination by humans and cattle, whereas C. andersoni was the most common parasite in wastewater. There may be geographic differences in the distribution of Cryptosporidium genotypes in surface water. The PCR-RFLP technique can be a useful alternative method for detection and differentiation of Cryptosporidium parasites in water.

https://aem.asm.org/content/aem/67/3/1097.full.pdf

Molecular Characterization of Cryptosporidium Oocysts in Samples of Raw Surface Water and Wastewater

Oocysts of Cryptosporidium parvum placed in artificial seawater at salinities of 10, 20, and 30 ppt at 10 degrees C and at 10 ppt at 20 degrees C were infectious after 12 weeks. Those placed in seawater at 20 ppt and 30 ppt at 20 degrees C were infectious for 8 and 4 weeks, respectively. These findings suggested that oocysts could survive in estuarine waters long enough to be removed by filter feeders such as oysters. Thereafter, 30 Eastern oysters, Crassostrea virginica, were collected with a dredge or with hand tongs at each of six sites within Maryland tributaries of the Chesapeake Bay in May and June and in August and September of 1997. Hemocytes and gill washings from all oysters were examined for the presence of Cryptosporidium oocysts and Giardia cysts by immunofluorescence microscopy utilizing a commercially available kit containing fluorescein isothiocyanate-conjugated monoclonal antibodies. Giardia was not detected by this method from any of the 360 oysters examined. Presumptive identification of Cryptosporidium oocysts was made in either hemocytes or gill washings of oysters from all six sites both times that surveys were conducted. In addition, during August and September, for each of the six sites, hemocytes from the 30 oysters were pooled and gill washings from the oysters were pooled. Each pool was delivered by gastric intubation to a litter of neonatal mice to produce a bioassay for oocyst infectivity. Intestinal tissue from two of three mice that received gill washings from oysters collected at a site near a large cattle farm and shoreline homes with septic tanks was positive for developmental stages of C. parvum. These findings demonstrate for the first time that oysters in natural waters harbor infectious C. parvum oocysts and can serve as mechanical vectors of this pathogen.

Survival of Infectious Cryptosporidium parvum Oocysts in Seawater and Eastern Oysters (Crassostrea virginica) in the Chesapeake Bay

Prevalence of Cryptosporidium, Giardia and Eimeria infections in post-weaned and adult cattle on three Maryland farms.

Human echinostomiasis, endemic to southeast Asia and the Far East, is a food-borne, intestinal, zoonotic parasitosis attributed to at least 16 species of digenean trematodes transmitted by snails. Two separate life cycles of echinostomes, human and sylvatic, efficiently operate in endemic areas. Clinical symptoms of echinostomiasis include abdominal pain, violent watery diarrhea, and anorexia. The disease occurs focally and transmission is linked to fresh or brackish water habitats. Infections are associated with common sociocultural practices of eating raw or insufficiently cooked mollusks, fish, crustaceans, and amphibians, promiscuous defecation, and the use of night soil (human excrement collected from latrines) for fertilization of fish ponds. The prevalence of infection ranges from 44% in the Philippines to 5% in mainland China, and from 50% in northern Thailand to 9% in Korea. Although the patterns of other food-borne trematodiases have changed in Asia following changes in habits, cultural practices, health education, industrialization, and environmental alteration, human echinostomiasis remains a health problem. The disease is most prevalent in remote rural places among low-wage earners and in women of child bearing age. Echinostomiasis is aggravated by socioeconomic factors such as poverty, malnutrition, an explosively growing free-food market, a lack of supervised food inspection, poor or insufficient sanitation, other helminthiases, and declining economic conditions. Furthermore, World Health Organization control programs implemented for other food-borne helminthiases and sustained in endemic areas are not fully successful for echinostomiasis because these parasites display extremely broad specificity for the second intermediate host and are capable of completing the life cycle without involvement of the human host.

Thaddeus K. Graczyk

Papers

Effects of environmental change on emerging parasitic diseases.

Molecular Characterization of Cryptosporidium Oocysts in Samples of Raw Surface Water and Wastewater

Survival of Infectious Cryptosporidium parvum Oocysts in Seawater and Eastern Oysters (Crassostrea virginica) in the Chesapeake Bay

Prevalence of Cryptosporidium, Giardia and Eimeria infections in post-weaned and adult cattle on three Maryland farms.

Echinostomiasis: a common but forgotten food-borne disease