Ecotoxicological evaluation the effects of the safe concentration of wastewater containing phenol on aquatic ecosystems

The aim of this study was to identify the toxicity, determine and verify safe concentration of effluents containing phenol to the aquatic ecosystems on the basis of single- and multispecies ecotoxicological bioassays. Synthetic wastewater imitating municipal sewage showed acute toxicity in relation to all bioindicators and belonged to the third toxicity class. The most sensible organism was Danio rerio, the most resistance organism was Desmodesmus quadricauda. Chronic safe concentration of wastewater containing phenol was 0.63% which corresponded to 0.63 mg/l of phenol. Appointed safe concentration and the one ten times higher than safe were verified in microcosm study, which confirmed that safe concentration did not cause toxic effects. Maximum permissible concentration of phenol in water bodies does not exceed determined concentration in different countries. Proposed research model can be used to determine and verify safe concentrations for aquatic ecosystems of many types of sewage from various industries

Effect of aluminium oxide nanoparticles on the enzymatic activity on microorganisms of activated sludge

The increased production and commercial use of nanoparticles (NPs), combined with a lack of regulation regarding their disposal, may result in the unwanted introduction of NPs to wastewater. Wastewater nutrient removal depends on the metabolisms of activated sludge bacteria and their related key enzymes. Therefore, the aim of this work was to determine the effect of aluminium oxide nanoparticles concentrations on the activated sludge enzymatic activity of microorganisms. Tested nanoparticles inhibition cellular respiration in TTC method in the four highest tested concentrations. Moreover, in most samples observed increase dehydrogenase activity. In this study, nano-Al2O3 also caused a clear stimulation of the activity of hydrolytic enzymes microorganisms of activate sludge. Effects of aluminum oxide (compound in bulk forms) on enzymatic activity were different than in the case of the nano from of Al2O3

Effects of aluminium oxide nanoparticles on bacterial growth

Production and wide application of nanomaterials have led to nanotechnology development but their release to environment and the induction of toxic reactions, affects the natural microbial communities. Therefore, studies on the impact of nanoparticles on microorganisms and environment are required and needed. The aim of this study was to assess the impact of aluminium oxide nanoparticles on the growth of Pseudomonas putida. To compare the harmfulness of different forms of aluminium oxide, the ecotoxicity of its macro-forms was also evaluated in the study. Research showed that the exposure to nanoparticles can negatively influence microorganisms. The EC50-16h determined in this study was 0.5 mg/l, and NOEC equaled 0.19 mg/l. Nano-Al2O3 proved to be more toxic to P. putida than aluminium oxide. This indicates that the nano-form of a given substance demonstrates different properties and may constitute a far greater danger for the environment than the same substance in the large form. According to EU and US EPA criteria, nano-Al2O3 proved to be very toxic and highly toxic, respectively. Changes in bacterial communities caused by nanoparticles may affect the normal biological, chemical and nutrient cycle in the ecosystem and the effect triggered by nanomaterials in relation to other organisms is unpredictable

The effect of zirconium oxide nanoparticles on dehydrogenase and hydrolytic activity of activated sludge microorganisms

The pervasive use of engineered nanoparticles (NPs) in a wide range of fields raises concerns about their potential environmental impacts. The impact of NPs on the activity of enzymes in sewage sludge was examined using model engineered zirconium oxide nanoparticles (nano-ZrO2). Dehydrogenase activity was evaluated with the TTC test and hydrolytic activity with FDA test. In this study an inhibitory or a stimulating effect of NPs on the activity of the enzymes was observed. The levels of inhibition/stimulation of the nano-ZrO2 varied in relation to duration of contact NPs with activated sludge and particle size (nano, bulk)

The effect of zirconium oxide nanoparticles on dehydrogenase and hydrolytic activity of activated sludge microorganisms

The pervasive use of engineered nanoparticles (NPs) in a wide range of fields raises concerns about their potential environmental impacts. The impact of NPs on the activity of enzymes in sewage sludge was examined using model engineered zirconium oxide nanoparticles (nano-ZrO2). Dehydrogenase activity was evaluated with the TTC test and hydrolytic activity with FDA test. In this study an inhibitory or a stimulating effect of NPs on the activity of the enzymes was observed. The levels of inhibition/stimulation of the nano-ZrO2 varied in relation to duration of contact NPs with activated sludge and particle size (nano, bulk)

Effects of aluminium oxide nanoparticles on bacterial growth

Production and wide application of nanomaterials have led to nanotechnology development but their release to environment and the induction of toxic reactions, affects the natural microbial communities. Therefore, studies on the impact of nanoparticles on microorganisms and environment are required and needed. The aim of this study was to assess the impact of aluminium oxide nanoparticles on the growth of Pseudomonas putida. To compare the harmfulness of different forms of aluminium oxide, the ecotoxicity of its macro-forms was also evaluated in the study. Research showed that the exposure to nanoparticles can negatively influence microorganisms. The EC50-16h determined in this study was 0.5 mg/l, and NOEC equaled 0.19 mg/l. Nano-Al2O3 proved to be more toxic to P. putida than aluminium oxide. This indicates that the nano-form of a given substance demonstrates different properties and may constitute a far greater danger for the environment than the same substance in the large form. According to EU and US EPA criteria, nano-Al2O3 proved to be very toxic and highly toxic, respectively. Changes in bacterial communities caused by nanoparticles may affect the normal biological, chemical and nutrient cycle in the ecosystem and the effect triggered by nanomaterials in relation to other organisms is unpredictable

Effect of aluminium oxide nanoparticles on the enzymatic activity on microorganisms of activated sludge

The increased production and commercial use of nanoparticles (NPs), combined with a lack of regulation regarding their disposal, may result in the unwanted introduction of NPs to wastewater. Wastewater nutrient removal depends on the metabolisms of activated sludge bacteria and their related key enzymes. Therefore, the aim of this work was to determine the effect of aluminium oxide nanoparticles concentrations on the activated sludge enzymatic activity of microorganisms. Tested nanoparticles inhibition cellular respiration in TTC method in the four highest tested concentrations. Moreover, in most samples observed increase dehydrogenase activity. In this study, nano-Al2O3 also caused a clear stimulation of the activity of hydrolytic enzymes microorganisms of activate sludge. Effects of aluminum oxide (compound in bulk forms) on enzymatic activity were different than in the case of the nano from of Al2O3

Adhesives based on formaldehyde – environmental problems

Adhesives are substances that increase the surface adhesion of bonded items. Unfortunately, they also emit volatile organic compounds (VOCs) which negatively impact upon human and animal health. VOCs have carcinogenic and mutagenic properties and can cause migraines, irritation to the eyes, nasal passages, mouth, and lungs, and respiratory problems. Wastewater from adhesive production is characterized by high levels of pollutants and contains high concentrations of compounds including formaldehyde that are toxic to water biocenoses. Moreover, its purification causes many problems and requires the application of specific methods. This review presents data concerning the toxicity and ecotoxicity of selected adhesives components. VOC emission rates from adhesives and wooden construction elements with adhesives are also discussed and assessed. Current knowledge on the treatment methods for wastewater containing adhesive components is reviewed. Finally, the treatment and disposal methods for solid wooden waste containing adhesives are also analyzed and discussed

Bioaerosol Emission from Biofilters: Impact of Bed Material Type and Waste Gas Origin

Three semi-technical scale biofilters were applied to treat waste gases at different industrial sites in Poland: a mechanical–biological treatment plant of municipal solid waste, a wastewater treatment plant and a food industry plant. Two types of materials were used as beds in the biofilters: stumpwood chips and pine bark, and stumpwood chips, pine bark and compost from green waste. Both bed materials supported the microbial growth and high numbers (106–108 cfu/g dry mass (DM)) of culturable bacteria, and fungi in beds were observed. There was no correlation between the number of microorganisms (cfu/g DM) and the respiratory activity in the biofilter beds. However, microbial respiration activity corresponded with microbial abundance expressed as microbial equivalents (ME), which was calculated based on adenosine triphosphate (ATP) determination. The biofilters either reduced or increased bioaerosol emissions from industrial plants, depending on the microbial content in the waste gases. A high microbial content in the waste gases made the effect of microbial emission from the biofilter bed negligible. The type of biofilter bed and number of microorganisms in the bed also influenced the final bioaerosol emission, but these factors were relevant for biofilters that treated waste gases with low microbial concentrations

Bioaerosol Emission from Biofilters: Impact of Bed Material Type and Waste Gas Origin

Three semi-technical scale biofilters were applied to treat waste gases at different industrial sites in Poland: a mechanical–biological treatment plant of municipal solid waste, a wastewater treatment plant and a food industry plant. Two types of materials were used as beds in the biofilters: stumpwood chips and pine bark, and stumpwood chips, pine bark and compost from green waste. Both bed materials supported the microbial growth and high numbers (106–108 cfu/g dry mass (DM)) of culturable bacteria, and fungi in beds were observed. There was no correlation between the number of microorganisms (cfu/g DM) and the respiratory activity in the biofilter beds. However, microbial respiration activity corresponded with microbial abundance expressed as microbial equivalents (ME), which was calculated based on adenosine triphosphate (ATP) determination. The biofilters either reduced or increased bioaerosol emissions from industrial plants, depending on the microbial content in the waste gases. A high microbial content in the waste gases made the effect of microbial emission from the biofilter bed negligible. The type of biofilter bed and number of microorganisms in the bed also influenced the final bioaerosol emission, but these factors were relevant for biofilters that treated waste gases with low microbial concentrations