Spatiotemporal distribution, ecological risk assessment, and human health implications of currently used pesticide (CUP) residues in the surface water of Feni River, Bangladesh.

Spatiotemporal monitoring of pesticide residues in river water is urgently needed due to its negative environmental and human health consequences. The present study is to investigate the occurrence of multiclass pesticide residue in the surface water of the Feni River, Bangladesh, using an optimized salting-out assisted liquid-liquid microextraction (SALLME) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). The optimized SALLME method was developed and validated following the SANTE/11312/2021 guidelines. A total of 42 water samples were collected and analyzed to understand the spatiotemporal distribution of azoxystrobin (AZ), buprofezin (BUP), carbofuran (CAR), pymetrozine (PYM), dimethoate (DMT), chlorantraniliprole (CLP), and difenoconazole (DFN). At four spike levels (n = 5) of 20, 40, 200, and 400 µg/L, the recovery percentages were satisfactory, ranging between 71.1 % and 107.0 % (RSD ≤13.8 %). The residues ranged from below the detection level (BDL) to 14.5 µg/L. The most frequently detected pesticide was DMT (100 %), followed by CLP (52.3809-57.1429), CAR (4.7619-14.2867), and PYM (4.7619-9.5238). However, AZ and BUP were below the detection limit in the analyzed samples of both seasons. Most pesticides and the highest concentrations were detected in March 2023, while the lowest concentrations were present in August 2023.Furthermore, ecological risk assessment based on the general-case scenario (RQm) and worst-case scenario (RQex) indicated a high (RQ > 1) risk to aquatic organisms, from the presence of PYM and CLP residue in river water. Human health risk via dietary exposure was estimated using the hazard quotient (HQ). Based on the detected residues, the HQ (<1) value indicated no significant health risk. This report provides the first record of pesticide residue occurrences scenario and their impact on the river environment of Bangladesh.

Method development of multi pesticide residue analysis in country beans collected from Dhaka, Bangladesh, and their dietary risk assessment.

The aim of the study was to develop a modified QuEChERS method coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the simultaneous determination of five multi-class pesticides in country beans collected from Dhaka, Bangladesh. Pesticides were extracted using ACN, and to minimize the co-extraction matrix, optimized d-SPE cleanup was done using sorbents (GCB, PSA, and C18). In the calibration range, the method showed excellent linearity with a correlation coefficient of R2 ≥ 0.9990 both in solvent- and matrix-matched calibration. For the selected pesticides, average recoveries (at four spiking levels (n = 5) of 10, 20, 100, and 200 µg/kg) of 70-100 % were achieved with relative standard deviations (RSDs) ≤ 9.5 %. The limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.3333 to 1.3333 µg/kg and 1.0 to 4.0 µg/kg, respectively. The dietary risk assessment, in terms of hazard quotient (HQ), was calculated to assess consumers' health risks.

Biometric indices and population parameters of three polynemid fishes from Batang Lassa Estuary of East Malaysia.

The length-weight relationships (LWRs), condition factor (Kn), growth, mortality and exploitation status of three polynemid fishes, i.e., Filimanus xanthonema (Valenciennes, 1831), Polynemus melanochir (Valenciennes, 1831) and Polynemus paradiseus (Linnaeus, 1758) from Batang Lassa River estuary were estimated. Fish samples were caught during April 2019 to September 2020 using the ESBN (locally called Gnian) having 1.25 to 4.00 cm mesh size. The total length (TL) and body weight of each individual fish was measured to the nearest 0.1 cm and 0.01 g respectively. The growth coefficients (b) for F. xanthonema, P. melanochir and P. paradiseus, were 2.880, 2.717 and 2.724 with the R 2 values 0.956, 0.972 and 0.936 respectively. Estimated growth coefficients indicated a negative allometric growth pattern for all three threadfin fishes. To date, information regarding length-weight relationships for F. xanthonema and P. melanochir is insufficient whereas the information is available for P. paradiseus. About 40-48% of fishes exhibited flat or thin body shape (Kn < 1), 48-50% were rounded or fat (Kn > 1) and only 1-3% of fishes showed proportional body shape (Kn = 1). The growth parameters L∞ , K and ϕ' were estimated at 15.75 cm, 0.95 yr-1 and 2.37 for F. xanthonema; 27.61 cm 0.87 yr-1 and 2.82 for P. melanochir; and 27.30 cm, 0.58 yr-1 and 2.64 for P. paradiseus; respectively. The estimated natural mortality (M) included 2.10, 1.69 and 1.30 yr-1; the fishing mortality (F) 0.57, 0.67 and 0.60 yr-1; and exploitation ratio (E) 0.21, 0.28 and 0.31 for F. xanthonema, P. melanochir and P. paradiseus respectively. The study concluded that the stocks are still under exploitation (E < 0.5) condition. However, the studied Batang Lassa estuary could be a potential nursery ground considering the minimum lengths of 5.0, 3.8 and 4.0 cm for F. xanthonema, P. melanochir and P. paradiseus respectively. Therefore, management initiatives are needed to escape juvenile catches.

Spatial distribution of manganese in groundwater and associated human health risk in the southern part of the Bengal Basin.

The scarcity of arsenic and iron-free safe drinking water is an alarming issue in the southern part of the Bengal Basin. The objectives of the present study were to investigate the spatial distribution of manganese (Mn) concentration in the shallow and deep groundwater and its associated health risks for the children and adults of entire southern Bengal Basin. The Mn concentration in the groundwater varied from 0 to 5.4 mg/L with an average value of 0.47 mg/L that exceeded the WHO's and Bangladesh drinking water guideline values of 0.4 and 0.1 mg/L, respectively. Mn concentration in the shallow wells overrode the deep ones. About 23% of the shallow wells and 11% of deep wells exceeded the WHO's safety limit of Mn concentration for human health. The human health risk related to Mn contamination was estimated by computing the average daily dosage (ADD) and hazard quotient (HQ) values for children and adults. The average computed HQ values found 0.108 and 0.099 for children and adults, respectively. The HQ values delimitated that children are posing a higher risk compared to the adults for the shallow wells. Deep wells were found risk-free for both children and adults. The areal coverage of shallow wells with HQ values > 1 was minimal compared to the total study area and covered only a small portion of Patuakhali and Barguna districts. The rest of the site does not pose any health risk due to Mn contamination for children and adults.

Spatiotemporal distribution of boron in the groundwater and human health risk assessment from the coastal region of Bangladesh.

High concentrations of naturally-occurring and man-accentuated boron in groundwater possess a potential threat to the health and well-being of humans worldwide. In Bangladesh, only a few studies focused on the health risks of boron-containing groundwater. Therefore, the present study investigated the spatiotemporal distribution of boron concentrations in groundwater and its associated health risks in the coastal districts of Bangladesh. A total of 268 samples from the shallow and deep wells during the wet and dry season (137 and 131 samples, respectively) were collected to determine the level of boron concentrations and health risk status. The groundwater boron concentrations ranged from 0 to 4.10 mg/L with an average concentration of 0.68 mg/L, which was much lower than the WHO and the values of Bangladesh drinking water standard guideline. The boron concentrations in the shallow wells override the deep ones with insignificant seasonal variation. Boron contamination affected 10% of the shallow wells in the wet season and only 6% of them in the dry season, whereas only 1% of deep wells exceeds the WHO guideline values of 2.40 mg/L during the wet and dry season, respectively. The human health risk of boron was determined by computing estimated daily intake (EDI) and hazard quotient (HQ) values for infants, children, teenagers, and adults. The average HQ value delimitated that children have high risk followed by teenagers, adults, and infants. About 90-95% of the studied samples were free from boron contamination because of having HQ values < 1 and the rest of the samples possess a high risk for children. For the overall study area, the deep wells were found safer than the shallow wells, which were more susceptible to boron contamination aided by localized freshwater inputs.

Study on ascitic fluid protein level in cirrhotic patients with spontaneous bacterial peritonitis.

Complement 3 is an important component of ascitic fluid total protein, which offers local defence against infection of the ascitic fluid. Hepatic synthesis of complement 3 as well as other proteins and their concentrations in ascitic fluid is significantly reduced in patients with advanced cirrhosis. The level of protein in ascitic fluid in cirrhotic patients with spontaneous bacterial peritonitis was compared with that in patients without spontaneous bacterial peritonitis. Ascitic fluid protein level in spontaneous bacterial peritonitis (n=15) was 1.1 +/- 0.3 g/dL whereas it was 1.5 +/- 0.5 g/dL in patients without spontaneous bacterial peritonitis (n=15). In conclusion, this study suggests that, ascitic fluid protein level is significantly (p = 0.008) reduced in cirrhotic patients who develop spontaneous bacterial peritonitis.