Soil toxicity in a protected area in Brazil: Cytotoxic, genotoxic, and toxic effects.

The Campos de Palmas Wildlife Refuge (CPWR) (Brazil) is a full protection Conservation Unit (CU) formed by private properties, where the use of land and natural resources are allowed sustainably according to the rules of the CU Management Plan. Inadequate practices of land use and occupation within this CU can affect its quality and the organisms that depend on them. Considering the above, the objective of the present study was to biomonitor different land uses and occupations within the CPWR and its surroundings, during the four seasons of a year, using the bioindicators Allium cepa (cytotoxicity and genotoxicity tests) and Eisenia fetida (leakage test). The soil samples were collected in areas of silviculture, agriculture, and native grasslands within the CU and agriculture outside the limits of the CPWR. The use by silviculture (spring) and native grassland (summer) showed cytotoxic effects for A. cepa. The use by agriculture outside the CPWR (spring) showed genotoxic effect and stimulation of mitotic cell division. For the animal bioindicator, the use by agriculture within the CPWR (winter), native grassland (autumn and spring), silviculture (autumn and spring), and agriculture outside the CU (spring) showed a toxic effect. A PCA analysis showed a correlation between the results of toxicity, cytotoxicity, and genotoxicity with the presence of macronutrients and metals in the evaluated soil samples. Possibly influenced by their soil composition characteristics (silviculture and native grassland) or the management of agricultural areas. In addition, samples from the rainy season (spring) showed higher ecotoxicity. These results show that biomonitoring through different organisms is important for evaluating environmental quality and indicate the need for the implementation of preventive measures in the CPWR to avoid the toxic, cytotoxic, and genotoxic effects found. They also ensure the integrity of this CU and the active protection of the environment and biodiversity.

Biomonitoring of surface water quality in the Chopim River within the Conservation Unit Campos de Palmas Wildlife Refuge, southern Brazil.

The Campos de Palmas Wildlife Refuge (RVS-CP) is a full protection conservation unit (CU) formed by private properties. The present study aimed to use the bioindicators Allium cepa L. (cytotoxicity and mutagenicity tests) and Eisenia fetida (avoidance test) to assess the quality of surface water of the Chopim River within the RVS-CP area and its surroundings during the four seasons of the year. To do so, water samples were collected at five points, four inside the RVS-CP area and a fifth point outside thereof. Samples from all sampling points had cytotoxic effect on A. cepa in at least one season of the year. Such a finding may be related to inadequate management practices (without land-use control) in the areas surrounding the sampling points such as forestry, native fields, pastures, agriculture, and housing areas. As for the animal bioindicator (E. fetida), only points 1 (in the winter) and 5 (in the autumn) were toxic. Concerning mutagenicity, points 1 and 4 (in the spring), 1 and 2 (in the summer), and 3 (in the autumn) showed mutagenic effect on A. cepa meristematic cells, therefore only within the RVS-CP area. Overall, these results show that biomonitoring can be an ally of the residents of the RVS-CP area in controlling management practices, aiming to bring together economic support and conservation of resources, especially water.

Cytotoxicity and mutagenicity of the waters of the Marrecas River (Paraná, Brazil) to bullfrogs (Lithobates catesbeianus).

Animals have a long history of assessing ecosystem responses to environmental disturbances, and amphibians stand out for presenting themselves as good animal model and bioindicators of environmental quality. The main purpose of the present work was to investigate the cellular effects of contamination of waters of the Marrecas River, located in the southwest of the state of Paraná, Brazil. Therefore, the objective of the present study was to investigate and monitor the cytotoxic and mutagenic effect, with bullfrog tadpoles, and to discuss these effects with land use along this hydrographic basin. Mutagenic effects were determined by micronucleus assay, and cytotoxicity by other nuclear changes, such as segmented cells, binucleated cells, cells with buds and reniform cells. Water samples were obtained at nine sites along the Marrecas River, covering areas with rural and urban hydrological contribution. For each site, four samples were collected, along the years 2017 and 2018, encompassing the four seasons (summer, autumn, winter, and spring). The results showed mutagenic and cytotoxic effect in four sampling sites, and only cytotoxic effect in other four sites. These effects may be due, possibly, to the use of different agrochemicals across the hydrographic basin region, which have predominant hydrological contributions from crops. Data of this study indicate the presence of cytotoxic and mutagenic contaminants in the waters of the Marrecas River, which can generate environmental problems on the river fauna/flora, and can also affect the local population health.