0000000001325271
AUTHOR
Anna K. Karjalainen
showing 14 related works from this author
Pollutant concentrations in placenta.
2011
Unborn children are exposed to environmental pollutants via the placenta, and there is a causal relationship between maternal intake of pollutants and fetal exposure. Placental examination is an effective way for acquiring data for estimating fetal exposure. We analyzed the concentrations of 104 congeners of persistent organic pollutants, seven organotin compounds, five heavy metals, and methylmercury in 130 randomly selected placentas. Additionally, we examined similarities between pollutant concentrations by analyzing correlations between their placental concentrations. Our results yield new information for conducting contaminant risk assessments for the prenatal period. Out of the 117 in…
Effects of docosahexaenoic acid and methylmercury on child's brain development due to consumption of fish by Finnish mother during pregnancy: A proba…
2011
Abstract Fish contains both beneficial substances e.g. docosahexaenoic acids but also harmful compounds e.g. methylmercury. Importantly, the health effects caused by these two substances can be evaluated in one common end point, intelligence quotient (IQ), providing a more transparent analysis. We estimated health effects of maternal fish consumption on child’s central nervous system by creating a model with three alternative maternal fish consumption scenarios (lean fish, fatty fish, and current fish consumption). Additionally, we analyzed impacts of both regular fish consumption and extreme fish consumption habits. At the individual level, the simulated net effects were small, encompassin…
Ecotoxicity assessment of boreal lake sediments affected by metal mining: Sediment quality triad approach complemented with metal bioavailability and…
2019
Highlights • Ecological risk assessment of metal-contaminated boreal lakes and sediments. • Sediment Quality Triad complemented with bioavailability and body residue studies. • Toxicity studies for natural sediments with several organisms and endpoints • Adverse effects observed. High variation on results between different methods. • Standard toxicity tests not suitable for testing, too low pH hampers the results. There are several methods for studying metal-contaminated freshwater sediments, but more information is needed on which methods to include in ecological risk assessment. In this study, we compliment the traditional Sediment Quality Triad (SQT) approach – including information on c…
Blackfly Larvae (Simulium spp.) Can Intensify Methylmercury Biomagnification in Boreal Food Webs
2020
AbstractGlobal pollution of mercury (Hg) threatens ecosystem and human health. We measured total Hg (THg) and monomethylmercury (MMHg) concentrations in filter-feeding blackfly (Simulium spp.) larvae in the inflows and the outflows of six boreal lakes with no Hg point source pollution. THg in the larvae ranged from 0.03 to 0.31 mg kg−1 dw and MMHg between 0.02 and 0.25 mg kg−1 dw. The proportion of MMHg in the larvae was 74 ± 0.16% and ranged from 43 to 98% of THg, the highest proportions being comparable to those typically found in aquatic predatory insects and fish. We compared the larvae MMHg concentrations to river water quality, catchment land-use, and to size-adjusted lake pike THg da…
Tolerance of whitefish (Coregonus lavaretus) early life stages to manganese sulfate is affected by the parents
2016
European whitefish (Coregonus lavaretus) embryos and larvae were exposed to 6 different manganese sulfate (MnSO4) concentrations from fertilization to the 3-d-old larvae. The fertilization success, offspring survival, larval growth, yolk consumption, embryonic and larval Mn tissue concentrations and transcript levels of detoxification-related genes were measured in the long-term incubation. Full factorial breeding design (4 females x 2 males) enabled examining the significance of both female and male effects, and female-male interactions in conjunction with the MnSO4 exposure on the observed endpoints. The MnSO4 exposure reduced the survival of the whitefish early life stages. Also the offs…
Toxicity of Mining-Contaminated Lake Sediments to Lumbriculus variegatus
2021
AbstractBoreal lakes with soft water and low buffering capacity are susceptible to excess ion loading resulting from metal mining. The impact of two Finish mining sites in downstream lakes was assessed with a chronic sediment toxicity test using a laboratory-reared freshwater Lumbriculus variegatus (Oligochaeta). The test organisms were exposed to mining-contaminated natural lake sediments and hypolimnion water (HLW) or artificial freshwater (AFW) as overlying water in two independent experimental setups. In both test setups, growth and reproduction of L. variegatus were lower in sediments from the lakes receiving high amount of mining effluents from the mines nearby. In the biomining site,…
Sulfate toxicity to early life stages of European whitefish (Coregonus lavaretus) in soft freshwater
2020
Sulfate occurs naturally in the aquatic environment but its elevated levels can be toxic to aquatic life in freshwater environments. We investigated the toxicity of sulfate in humic, soft freshwater to whitefish (Coregonus lavaretus) from fertilization of eggs to hatching i.e. during the critical phases of whitefish early development. Anadromous Kokemäenjoki whitefish eggs and sperm during fertilization, embryos and larvae were exposed in the long-term 175-day incubation to seven different sodium sulfate (Na2SO4) concentrations from 44 to 2 000 mg SO4 L−1. Endpoint variables were the fertilization success, offspring survival and larval growth. Egg fertilization and early embryonic developmen…
Condition and Sperm Characteristics of Perch Perca fluviatilis inhabiting Boreal Lakes Receiving Metal Mining Effluents.
2020
AbstractOne of the world’s largest, but low-grade, sulfide nickel deposits in northeastern Finland has been exploited by a bioheapleaching technology since 2008. Bioheapleaching is a relatively new, cost-effective technology, but humid climate, e.g., in boreal temperate environments, causes challenges to the management of the water balance in the ore heaps with wide catchment area, and the mining effluents have caused substantial metal and salting contamination of the receiving waterbodies. In our study, the impacts of metal-extracting bioheapleaching mine effluents on muscle and liver element concentrations, body condition, liver and testes mass, and sperm count and motility of male perch …
Toxicity of biomining effluents to Daphnia magna: Acute toxicity and transcriptomic biomarkers
2018
Increasing metal consumption is driving the introduction of new techniques such as biomining to exploit low grade ores. The biomining impacts notably aquatic ecosystems, yet, the applicability of ecotoxicological tests to study the complex mixture effects of mining waters is insufficiently understood. The aim of the present work was to test if transcriptomic biomarkers are suitable and sensitive for the ecotoxicity assessment of biomining affected waters. The study site had been affected by a multimetal biomine, and the studied water samples formed a concentration gradient of contamination downstream from the biomining site. Cadmium and nickel were used as positive controls in the toxicity …
Estimated intake levels for Finnish children of methylmercury from fish
2013
Abstract Methylmercury (MeHg) is a well-known neurotoxic agent, and consumption of contaminated fish is the principal environmental source of MeHg exposure in humans. Children are more susceptible to adverse effects than adults. No previous specific data exist for intake by Finnish children of methylmercury from fish. We estimated fish consumption and MeHg intakes from species most commonly consumed by Finnish children aged 1–6 years. The total mercury concentrations were determined in fish species consumed, and age-specific methylmercury intakes were derived. We also examined safety margins and the proportion of children exceeding the tolerable daily intakes set by international expert bod…
Lumbriculus variegatus (Annelida) biological responses and sediment sequential extractions indicate ecotoxicity of lake sediments contaminated by bio…
2018
Abstract We assessed potential ecotoxicity of lake sediments affected by biomining effluents in northeastern Finland. Growth, reproduction and behavior of the sediment-dwelling oligochaete Lumbriculus variegatus (Muller 1774) were used as ecotoxicity endpoints. Standardized chronic bioassays were used for growth and reproduction, and acute and chronic tests with Multispecies Freshwater Biomonitor (MFB) for behavior assessments. Sequential extractions were used to characterize metal bioavailability and exposure conditions in the sediments, which indicated mining-induced contamination gradients of S, Cu, Ni and U and also bioavailability gradients of S and Ni. Among the ecotoxicity endpoints,…
Particle balance and return loops for microplastics in a tertiary-level wastewater treatment plant.
2021
Highlights: Dewatering by centrifugation was a step that removed a high number of MPs from the sludge. Sludge retained especially the fibrous microplactics. Reject water transported microplastics inside a wastewater treatment plant. Disc filter-based tertiary treatment ensured removal of 99% of microplastics in wastewater. Microplastics (MPs) from households, stormwater, and various industries are transported to wastewater treatment plants (WWTPs), where a high proportion of them are captured before discharging their residuals to watersheds. Although recent studies have indicated that the removed MPs are mainly retained in wastewater sludge, sludge treatment processes have gained less atten…
Optical Monitoring of Microplastics Filtrated from Wastewater Sludge and Suspended in Ethanol.
2021
The abundance of microplastics (MPs) in the atmosphere, on land, and especially in water bodies is well acknowledged. In this study, we establish an optical method based on three different techniques, namely, specular reflection to probe the medium, transmission spectroscopy measurements for the detection and identification, and a speckle pattern for monitoring the sedimentation of MPs filtrated from wastewater sludge and suspended in ethanol. We used first Raman measurements to estimate the presence and types of different MPs in wastewater sludge samples. We also used microscopy to identify the shapes of the main MPs. This allowed us to create a teaching set of samples to be characterized …
Original data for article: Particle balance and return loops for microplastics in a tertiary-level wastewater treatment plant
2020
Microplastics (MPs) from households, stormwaters and various industries are transported to wastewater treatment plants (WWTPs) where a high proportion of them are captured before discharging their residuals to watersheds. Although recent studies have indicated that the removed MPs are mainly retained in wastewater sludge, sludge treatment processes have gained less attention in MP research compared to water streams at primary, secondary and tertiary treatments. In this study, we sampled twelve different phases in a tertiary-level municipal WWTP in Central Finland. Our results showed that compared to plant influent load, three times higher number of MPs was circulating via reject water from …