Recipient Organization
UNIV OF MARYLAND
(N/A)
COLLEGE PARK,MD 20742
Performing Department
Wye Res And Education Center
Non Technical Summary
Human impacts on the environment and consequent stressors to ecosystem integrity have accelerated dramatically since the beginning of the industrial revolution. Multi-stressor anthropogenicimpacts, such as habitat destruction, modification of vegetative structure, increase in impervious surfaces due to urbanization, introduction of invasive species, and exposure to contaminants such as pesticides used in agriculture often cause population-level changes to aquatic biota. This Hatch project will encompass a suite of fieldand laboratory studies within aquatic ecosystems to investigate several of these anthropogenic impacts and assess their effects on ecosystem integrity, environmental health and possible management/control solutions. We have three tasks that address both non-point and point sources of pollution related to this theme. Task One will investigate the impacts of multiple chemical (i.e. insecticides) and non-chemical (i.e. physical habitat) stressors from both agricultural and urban non-point sources on resident benthic macroinvertebrate communities. Resident benthic communities are subjected to an array of both chemical and non-chemical stressors so multiple stressor analysis is important for teasing out the most significant stressors. Task Two will study the potential impacts of point source discharges from large industrial and municipal facilities on aquatic biota. The lethal and sublethal toxic effects from various chemical groups and municipal/industrial discharges will be evaluated. Task Three will investigate the aquatic toxicity of disinfection byproducts discharged as a point source from electrochlorination ballast water treatment systems designed to remove invasive species from cargo ships. Discharge from international ship ballast water tanks is one of the leading causes of invasive species world-wide. Many of the treatment systems approved to control invasive species use chlorine as the additive to eliminate these invasive species. Chlorine is also used extensively in wastewater treatment plants, power plants, and pulp and paper mills and disinfection byproducts can be found in effluents from these facilities. These discharges may mix with runoff from agricultural fields so information on toxicity from electrochlorination of ballast water would be transferrable to these other discharges when multi-stressor effects on ecosystems are considered. The outcomes of all three tasks will produce knowledge useful for making informed management decisions and formulating sustainable control solutions for reducing current and future threats from both non-point and point sources to environmental and human wellbeing.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
The common thread to the proposed research is an effort to better understand the complex interplay of anthropogenic stressors on ecosystem integrity and the consequent impact dissolution of this integrity has on human environmental health and wellbeing. The three tasks described below integrate research from both non-point and point sources of pollution. The overall goal of the multiple stressor task is to determine the impacts of multiple chemical and non-chemical stressors such as pyrethroids (a class of insecticides), metals, physical habitat, and sediment characteristics on resident benthic communities in wadeable streams as a result of both agricultural and urban non-point sources. The overall goal of the point source discharge task is to evaluate the toxicity of point sources discharges from various facilities in the State of Maryland. The study will evaluate the toxic effects from various chemical groups and effluent discharges to representative invertebrates and vertebrates that occur in both freshwater and estuarine ecosystems. The overall goal of the ballast water task is to help determine control measures to reduce/eliminate the damage to ecosystems from the point source discharge of disinfection byproducts from electrochlorination ballast water treatment systems.
Project Methods
Multiple Stressor Task: The multiple stressor task will include both field testing and statistical analysis of existing data bases where multiple chemical and non-chemical stressors have been evaluated in both agricultural and urban wadeable streams concurrently with the collection of benthic macroinvertebrates. Benthic communities will be sampled using a standard D-net approach targeting best available habitat at three transects per stream site. A maximum of 300 individuals per site will be identified to the lowest taxa possible and a series of benthic metrics that evaluate richness, composition, tolerance/intolerance, and trophic status will be developed from this data set. Physical habitat will be assessed at each stream site that include the following metrics: epifaunal substate; embeddedness; velocity depth diversity; sediment deposition; channel flow status; channel alteration; frequency/bends riffles; bank stability; vegetative protection; riparian zone and total score. Eight pyrethroids and eight metals will also be measured in sediment at each site. Total organic carbon and grain size (% sand, % silt and % clay) will also be measured in sediment at each site. In addition, basic water quality parameters will also be evaluated at each site.Multiple year data sets will be analyzed using a series of both univariate and multivariate techniques and various stressors and benthic metrics will be ranked high (most important) to low (least important). Power analysis from this multiple year data set will also be conducted to determine how power to detect significant relationships between benthic metrics and stressors change with increased sample size (i.e., how many samples need to be collected for studies across geographic areas to minimize type II errors that indicate there are no significant effect when there are, in fact, significant effects). Multivariate patterns of sampling sites with respect to benthic metrics and environmental stressors will also be determined and discussed within the context of North America Ecoregions and subecoregions.Point Discharge Task:The point source discharge task will evaluate the toxicity to various freshwater and estuarine invertebrate (crustaceans) and vertebrate (fish) species exposed to municipal and industrial discharges and to the chemical groups listed below. Both lethal and sublethal toxic effects (e.g., growth, brood production, fecundity, developmental toxicity, and other endpoints depending on the species) will be used in the evaluation. U.S. Environmental Protection Agency (EPA) protocols (EPA-821-R-02-012; EPA-821-R-02-013; and EPA-821-R-02-014) will used for the lethal and sublethal evaluations. Lethality will be determined in both acute (48 to 96 hours) and short-term chronic (7 days) exposures. Sublethal endpoints will be determined in 7-day exposures. Freshwater neonate cladocerans (Ceriodaphnia dubia) and immature estuarine mysids (Americamysis bahia) will be used as representative food chain organisms. The freshwater larval fathead minnow (Pimephales promelas) and swim-up fry rainbow trout (Oncorhynchus mykiss) will be evaluated as representative fish. The larval sheepshead minnow (Cyprinodon variegatus) will be evaluated as the estuarine species. The following chemical groups will be analyzed in the point source effluents: heavy metals (EPA 200.8); hexavalent chromium (S3500CeB-09); mercury (EPA 245.1); cyanide (amenable S4500CNG-09 and total EPA335.4), volatile organics (e.g., benzenes, ethenes, ethanes, vinyl chloride, etc. and their isomers) (EPA 624); semivolatiles (e.g., anthracenes, chlorobenzenes, phthalates, etc. and their isomers) (EPA 625), pesticides and PCBs (EPA 608); dioxins, and asbestos. The data from the evaluations will provide toxicity information useful for predicting potential impacts to local freshwater and estuarine ecosystems. In addition, the data can be used to evaluate and update current U.S. Environmental Protection Agency (U.S. EPA) and Maryland Department of the Environment regulatory water quality criteria standards which are several years old in a number of cases.Ballast water Task: The ballast water task will evaluate the toxicity of disinfection byproducts formed when electrochlorination is used to treat ballast water to remove invasive species. One of the major species of concern is single cell algae (plants) which are a major primary producer in estuarine and oceanic ecosystems. Toxicity of these disinfection byproducts to algae could disrupt the functioning of these ecosystems since algae represent the base of the food chain. Preliminary research at the University of Maryland's Wye Research and Education Center has shown that some algae species are extremely sensitive to the disinfection byproducts formed when chlorine is used to treat ballast water. Toxicity will be determined using algae toxicity methods developed by the United Nation's International Maritime Organization and consistent with methods approved by the U.S. Environmental Protection Agency and the American Society for Testing and Materials.Endpoints will include both algae survival and population growth. The various disinfection byproducts used in the testing will be produced in the laboratory or collected from actual treatment systems used for shipboard testing of ballast water treatment systems in Chesapeake Bay. A dilution series of at least five concentrations will be used in each test so that a No Observed Effect Concentration (NOEC), a Lowest Observed Effect Concentration (LOEC) and the test concentration that inhibits population growth by 25% (IC25) and 50% (IC50) can be calculated. The toxicity endpoint in these algae tests is cell growth measured as cells/mL (i.e., population growth) over 96 hours. This algae toxicity method is the only true measure of population growth in the U.S. EPA's suite of regulatory toxicity tests. The various disinfection byproducts used in the testing will be prepared in the laboratory or collected from actual treatment systems used for shipboard testing of ballast water treatment systems in Chesapeake Bay. In previous research we have analyzed for a suite of 26 disinfection byproducts in actual ballast water discharges and have found 13 which were routinely found above method detection limits. These will be the focus of the proposed toxicity research.