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2021 ◽  
Vol 2 (2) ◽  
pp. 49-55
Author(s):  
Gunawan Pratama Yoga ◽  
Kristin Noni Riyanti Buraen ◽  
Sutanto Sutanto

Ammonia is one of the nutrient wastes products which can be toxic to all vertebrates, including fish. Usually, ammonia toxicity is expressed as Total Ammonia Nitrogen (TAN, mgN/L). Tambra fish (Tor tambroides) is freshwater fish with important economic value in some areas in Indonesia. According to overfishing and forest degradation, the fish has become threatened. This research aimed to calculate the LC50 value of ammonia to Tambra fish (Tor tambroides) and estimate  NOEC,  LOEC, and MATC values of ammonia to Tambra fish (Tor tambroides). This study was conducted using the static test method with two steps. The first stage is a preliminary test, where the preliminary test is observed for 24 hours With five concentrations excluding control. Whereas in the second stage that is carried out, observation for 96 hours with four concentrations excluding control. The Probit test is Performed to obtain LC50 value results, then proceed with ammonia analysis using the Salicylate Test Kit method. The results showed that ammonia had acute toxicity with LC50-96 hour value of NH4Cl against Tambra fish fry (Tor tambroides) in the amount of 354.615 mg/L. Ammonia caused acute toxicity to Tambra fish fry (Tor tambroides).The LC50-96 hour value was 354.615 mg/L in the form of Total Ammonia Nitrogen (TAN) or it was equivalent to un-ionized Ammonia (NH3) of 9.8937 mg/L, while values of the Lowest Observed Effect Concentration (LOEC) and No Observed Effect Concentration (NOEC) of ammonia on Tambra fish (Tor tambroides) were 578.24 mg/L and 280.18 mg/L, respectively.


2021 ◽  
Author(s):  
Tomoki Takeda ◽  
Shotaro Yamano ◽  
Yuko Goto ◽  
Shigeyuki Hirai ◽  
Yusuke Furukawa ◽  
...  

Background: In Japan, six workers handling cross-linked water-soluble acrylic acid polymer (CWAAP) at a chemical plant suffered from lung diseases, including fibrosis, interstitial pneumonia, emphysema, and pneumothorax. We recently demonstrated that inhalation of CWAAP-A, one type of CWAAP, causes pulmonary disorders in rats. It is important to investigate dose-response relationships and recoverability from exposure to CWAAPs for establishing occupational health guidelines, such as setting threshold limit value for CWAAPs in the workplace. Methods: Male and female F344 rats were exposed to 0.3, 1, 3, or 10 mg/m3 CWAAP-A for 6 hours/day, 5 days/week for 13 weeks using a whole-body inhalation exposure system. At 1 hour, 4 weeks, and 13 weeks after the last exposure the rats were euthanized and blood, bronchoalveolar lavage fluid, and all tissues including lungs and mediastinal lymph nodes were collected and subjected to biological and histopathological analyses. In a second experiment, male rats were pre-treated with clodronate liposome or polymorphonuclear leukocyte-neutralizing antibody to deplete macrophages or neutrophils, respectively, and exposed to CWAAP-A for 6 hours/day for 2 days. Results: CWAAP-A exposure damaged only the alveoli. The lowest observed adverse effect concentration (LOAEC) was 1 mg/m3 and the no observed adverse effect concentration (NOAEC) was 0.3 mg/m3. Rats of both sexes were able to recover from the tissue damage caused by 13 weeks exposure to 1 mg/m3 CWAAP-A. In contrast, tissue damage caused by exposure to 3 and 10 mg/m3 was irreversible due to the development of interstitial lung lesions. There was a gender difference in the recovery from CWAAP-A induced pulmonary disorders, with females recovering less than males. Finally, acute lung effects caused by CWAAP-A were significantly reduced by depletion of alveolar macrophages. Conclusions: Pulmonary damage caused by inhalation exposure to CWAAP-A was dose-dependent, specific to the lung and lymph nodes, and acute lung damage was ameliorated by depleting macrophages in the lungs. CWAAP-A had both a LOAEC and a NOAEC, and tissue damage caused by exposure to 1 mg/m3 CWAAP-A was reversible: recovery in female rats was less than for males. These findings indicate that concentration limits for CWAAPs in the workplace can be determined.


2021 ◽  
Vol 16 (4) ◽  
pp. 340-346
Author(s):  
R. R. Dapawole ◽  
I. P. Sirappa

This study aimed to determine the effectiveness and the best concentration of Moringa leaf extract (MLE) in the citrate-egg yolk (C-EY) to maintain the motility and viability of spermatozoa kacang goat. Semen was collected from 3 goats aged two years; by using the artificial vagina method. The semen was evaluated macroscopically and microscopically. The semen that had >70% sperm motility and >250x106/ml sperm concentration was divided into 4 equal tubes, each diluted with100% C-EY (P1), 10% MLE+ 90%C-EY (P2), 20% MLE +80% C-EY (P3), and 30% MLE+70% C-EY (P4). The diluted samples were then stored in a refrigerator (3-5?C) and evaluated for motility and viability every 24 hours. The study was designed using a completely randomized design (CRD) consisting of four treatments and five replications. The results showed that the addition of MLE in C-EY significantly affected goat spermatozoa's progressive motility and viability. The data showed that the spermatozoa kept during four days in a diluent of P2 had higher (P<0.05) motility 44.67±4.80% and viability 74.24±4.46%than the other three diluents of P1(36.00±4.70%; 70.10±3.6%), P3(33.67±0.42%; 66.85±4.99%) and P4 (29.67±3.99%; 63.96±5.44%). This study concluded that adding 10% MLE was the best concentration as source energy in 90% C-EY diluents, which effectively maintained the motility and viability of kacang goat spermatozoa for four days of storage at a temperature of 3-5oC.


2021 ◽  
Author(s):  
Yue Wang ◽  
Tianyi Zhao ◽  
Xianhai Yang ◽  
Huihui Liu

Abstract As one of the alternatives of 2,2-bis(4-hydroxyphenyl)propane (bisphenol A, BPA), 2,2-bis(4-hydroxyphenyl)butane (bisphenol B, BPB) has not gained sufficient concerns so far, due to the limited concentration and toxicity data available. In this study, the acute toxicity of BPB to three aquatic organisms, i.e., Tetradesmus obliquus, Daphnia magna and Danio rerio, was investigated, and it showed that Daphnia magna was the most sensitive organism with the half effective concentration (EC50) of 3.93 mg/L. Thereout, the screened Daphnia magna was exposed to BPB for 21 days to explore the chronic toxicity. Results indicated that BPB restricted the body length of parent Daphnia magna and reduced the total number of broods and neonates. The no-observed effect concentration of BPB to Daphnia magna was as low as 0.01 mg/L, which was two orders of magnitude lower than that reported 0.86–5.00 mg/L of BPA. Furthermore, the ecological risk of BPB was quantitatively assessed using the risk quotient (RQ) method. Obviously, although the environmental concentrations and detectable rate of BPB were much lower than that of BPA, its ecological risk was not necessarily lower. Hence, BPB should not be ignored in the future environmental monitoring and management.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Magena Marzonie ◽  
Florita Flores ◽  
Nora Sadoun ◽  
Marie C. Thomas ◽  
Anais Valada-Mennuni ◽  
...  

AbstractOver 30 herbicides have been detected in catchments and waters of the Great Barrier Reef (GBR) and their toxicity to key tropical species, including the coral endosymbiotic algae Symbiodiniaceae, is not generally considered in current water quality guideline values (WQGVs). Mutualistic symbionts of the family Symbiodiniaceae are essential for the survival of scleractinian corals. We tested the effects of nine GBR-relevant herbicides on photosynthetic efficiency (ΔF/Fm′) and specific growth rate (SGR) over 14 days of cultured coral endosymbiont Cladocopium goreaui (formerly Symbiodinium clade C1). All seven Photosystem II (PSII) herbicides tested inhibited ΔF/Fm′ and SGR, with toxicity thresholds for SGR ranging between 2.75 and 320 µg L−1 (no effect concentration) and 2.54–257 µg L−1 (EC10). There was a strong correlation between EC50s for ΔF/Fm′ and SGR for all PSII herbicides indicating that inhibition of ΔF/Fm′ can be considered a biologically relevant toxicity endpoint for PSII herbicides to this species. The non-PSII herbicides haloxyfop and imazapic did not affect ΔF/Fm′ or SGR at the highest concentrations tested. The inclusion of this toxicity data for Symbiodiniaceae will contribute to improving WQGVs to adequately inform risk assessments and the management of herbicides in tropical marine ecosystems.


Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2885
Author(s):  
Nguyen Van Cong ◽  
Dinh Thai Danh ◽  
Tran Sy Nam

Chlorpyrifos ethyl is a popular insecticide widely used in agriculture within the Vietnamese Mekong delta, including for rice farming. Here, local farmers often apply pesticides at very high rates which leads to contamination of the surrounding environment. Silver barb (Barbonymus gonionotus) is a fish species indigenous to the delta, which resides in a variety of water bodies and is also commonly cultivated in rice–fish systems. As a result, this species is at high risk of exposure to chlorpyrifos ethyl. This study aims to determine the lethal concentration (LC50) of chlorpyrifos ethyl, as well as the effects of sub-lethal concentrations on the activity of cholinesterase and growth of Silver barb. Lethal concentration testing was conducted in a static non-renewed system. Three concentrations of chlorpyrifos ethyl (1%, 10% and 20% LC50-96 h) were conducted in triplicate to assess the effects of chlorpyrifos ethyl on the brain cholinesterase (ChE) of fingerling fish for 15 days, and on their growth for 60 days. Results showed that chlorpyrifos ethyl was highly toxic to fingerling Silver barb with a LC50-96 h of 0.119 ppm. The lowest observed effect concentration (LOEC) was 1%LC50-96 h for ChE and 10%LC50-96 h for growth. No observed effect concentration (NOEC) of chlorpyrifos ethyl for growth was 1%LC50-96 h. The result from this study suggests that ChE activity is significantly inhibited at environmentally realistic concentrations in the Vietnamese Mekong delta and can be used as a biomarker of pesticide exposure. Further study in the rice fields as well as in the canals or rivers is required.


2021 ◽  
Vol 16 (1) ◽  
pp. 19-25
Author(s):  
Pauly G.F.E. ◽  
Vallim A.L. ◽  
Merguizo R.A.C. ◽  
Daniel G. ◽  
Ramaglia A.C. ◽  
...  

The environmental effects caused by selective serotonin reuptake inhibitor drugs have been investigated for marine organisms and coastal ecosystems but are scarce in neotropical organisms. This investigation aimed to evaluate the sublethal effects of fluoxetine on the embryonic development of the sea urchin Echinometra lucunter and the survival and swimming behavior of the brine shrimp Artemia sp. The organisms were exposed to four different concentrations of fluoxetine (30, 300, 3000 and 30000 ng L-1) and to a negative control (filtered seawater), following the respective standard testing protocols. We verified a significant reduction of the embryos development to pluteus larvae, starting from 3000 ng L-1 (54.0±10.9% normal larvae), in comparison with the controls (83.5±3.1%). The non-observed effect concentration (NOEC) was estimated at 300 ng L-1, and the lowest observed effect concentration (LOEC) was 3000 ng L-1. In the behavior tests with Artemia sp, no significant adverse effects were reported for mobility, swimming speed and inactivity time. These results show that Fluoxetine can interfere on the development of species like the sea urchin E. lucunter, but short term exposure did not affected the swimming behavior of the brine shrimp Artemia sp. Fluoxetine presents thus a potential to affect marine biota and disrupt the equilibrium of the coastal ecosystems.


2021 ◽  
Author(s):  
Deng Xiru ◽  
Jiang Yingnan ◽  
Xian Qiming

Abstract The toxic effects of Lindane (γ-BHC) on Microcystis aeruginosa were studied under lab culture conditions. Total protein levels, as well as malondialdehyde (MDA) levels and superoxide dismutase (SOD) enzyme activity, in algal cells, were determined after exposure to different concentrations of Lindane. The bioaccumulation of Lindane, as well as the influence of pH and dissolved organic matter (DOM), on the toxic effects was also evaluated in algal cells. The growth of M. aeruginosa was inhibited by Lindane treatment (96 h), resulting in 50% of maximal effect (EC50) concentration of 442 μg/L. In addition the lowest observed effect concentration (LOEC) was found to be 120 μg/L, the no observed effect concentration (NOEC) 60 μg/L, and the maximum acceptable toxicant concentration (MATC) 85 μg/L. With increasing concentrations of Lindane and exposure time, M. aeruginosa growth was significantly inhibited; in addition, total protein levels and SOD activity significantly decreased. MDA concentration, however, showed an insignificant increase after 96 h. Lindane has the potential for bioaccumulation in algal cells with a bioconcentration factor (BCF) of 340. Furthermore, the toxic effects of Lindane on M. aeruginosa were influenced by environmental factors, such as pH and DOM. The toxic effects decreased with increasing pH and humic acid concentrations. Ultrastructure cell images were used to depict Lindane induced apoptosis.


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