Isolation and Identification of Naegleria Species in Irrigation Channels for Recreational Use in Mexicali Valley, Mexico

Members of the genus Naegleria are free-living amoebae that are widely distributed in water and soil environments. Moreover, Naegleria fowleri is a pathogenic amoeba species that causes a fatal disease in the central nervous system known as primary amoebic meningoencephalitis (PAM) in humans. Since most reported infections due to N. fowleri are reported in recreational waters worldwide, this study was aimed to describe the presence of these amoebic genus in Mexicali Valley irrigation channels of recreational use. A total of nine water samples were collected and processed by triplicate, in nine different sites of the Valley. After filtering and culturing the samples, plates were examined, and the observed amoebae were morphologically identified at the genus level. In addition, the pathogenicity of these amoebic isolates was checked, and molecular characterization was performed by PCR/sequencing. The results revealed the presence of Naegleria spp. in all the channels sampled. Finally, molecular identification confirmed the presence of five different species of Naegleria: N. fowleri, N. australiensis, N. gruberi, N. clarki and N. pagei. The presence of these protists, particularly N. fowleri, should be considered as a potential human health risk in the region.

Download Full-text

Heavy metals in aquatic organisms of different trophic levels and their potential human health risk in Bohai Bay, China

Environmental Science and Pollution Research ◽

10.1007/s11356-016-6948-y ◽

2016 ◽

Vol 23 (17) ◽

pp. 17801-17810 ◽

Cited By ~ 23

Author(s):

Yan Zhang ◽

Xueqiang Lu ◽

Naili Wang ◽

Meinan Xin ◽

Shiwei Geng ◽

...

Keyword(s):

Heavy Metals ◽

Health Risk ◽

Human Health ◽

Human Health Risk ◽

Aquatic Organisms ◽

Trophic Levels ◽

Bohai Bay ◽

Potential Human Health Risk ◽

Potential Human Health

Download Full-text

Arsenic Speciation in Rice, Mechanisms and Associated Health Risk Through Rice Consumption in Various Districts of Khyber Pakhtunkhwa, Pakistan

10.21203/rs.3.rs-262560/v1 ◽

2021 ◽

Author(s):

Tasneem Sarwar ◽

Sardar Khan ◽

Said Muhammad ◽

Javed Nawab ◽

Shehla Amin ◽

...

Keyword(s):

Health Risk ◽

Human Health ◽

Human Health Risk ◽

Daily Intake ◽

Mining Activities ◽

Khyber Pakhtunkhwa ◽

Icp Ms ◽

Rice Samples ◽

Potential Human Health Risk ◽

Potential Human Health

Abstract Arsenic (As) is one of the toxic metalloids therefore can cause health risk in the consumers through consumption of contaminated food and rice. The current study focused on As speciation in rice, bioavailability, mechanisms and its potential human health risk. For this purpose, rice and soil samples were collected from 16 different districts (non-mining and mining) of Khyber Pakhtunkhwa (Pakistan). Soil physicochemical characteristic such as texture, electrical conductivity (EC), organic matter (OM), pH, iron (Fe) and phosphorus (P) were determined. Total arsenic (AsT) concentrations were analyzed using ICP-MS, while the arsenite (As3+), arsenate (As5+), arsenobetine (BAs), dimethylarsenic (DMA) and monomethyl arsenic (MMA) were determined by HPLC–ICP-MS method. Results showed the highest AsT (0.28 mg/kg) was observed in the rice samples of DI Khan District and lowest (0.06 mg/kg) in Shangla District. However, these findings were found within the permissible limits set by various authorities. Furthermore, results showed higher concentrations of inorganic As (Asi) than organic As (Aso) species in rice. The estimated daily intake (EDI) and incremental lifetime cancer risk (ILTCR) were used to evaluate the potential human health risk for As consumption in rice. Results revealed that the rice samples collected from the district having mining activities had higher value of As (0.28 mg/kg of AsT) as compared to non-mining (0.072 mg/kg of AsT). The highest ILTCR value (0.00196) was observed for rice collected from mining districts. This study revealed that mining activities have great influence on the As contamination of soil and grown rice. This study recommends the soil amendment in districts having mining activities to lower As availability in soil and its bioaccumulation in growing rice that will help to keep lower the potential risk.

Download Full-text

Potential human health risk assessment of cylindrospermopsin accumulation and depuration in lettuce and arugula

Harmful Algae ◽

10.1016/j.hal.2017.08.010 ◽

2017 ◽

Vol 68 ◽

pp. 217-223 ◽

Cited By ~ 11

Author(s):

Micheline Kézia Cordeiro-Araújo ◽

Mathias Ahii Chia ◽

Maria do Carmo Bittencourt-Oliveira

Keyword(s):

Risk Assessment ◽

Health Risk ◽

Human Health ◽

Health Risk Assessment ◽

Human Health Risk ◽

Human Health Risk Assessment ◽

Potential Human Health Risk ◽

Potential Human Health

Download Full-text

TaGST1 Gene and Its Regulatory Factor WRKY74 Mediate Copper Tolerance by Effecting Glutathione Accumulation in Wheat

10.21203/rs.3.rs-136445/v1 ◽

2020 ◽

Author(s):

Ge-Zi Li ◽

Yong-Xing Zheng ◽

Shi-Juan Chen ◽

Jin Liu ◽

Peng-Fei Wang ◽

...

Keyword(s):

Human Health Risk ◽

Copper Tolerance ◽

Regulatory Factor ◽

Plant Growth And Development ◽

Glutathione S Transferase ◽

Cu Stress ◽

Key Enzyme ◽

Mda Content ◽

Potential Human Health Risk ◽

Potential Human Health

Abstract Background: Copper (Cu) is an important plant micronutrient; however, excessive Cu can disturb the protein structure, affect plant growth and development, and pose as a potential human health risk. Glutathione S-transferase (GST) is the key enzyme in glutathione (GSH) synthesis; it plays crucial role in Cu detoxification. Nonetheless, its regulatory mechanisms remain largely unclear.Results: A Cu-induced TaGST1 gene had been identified in this study. And the regulatory factor TaWRKY74 had been screen out by Yeast one-hybrid (Y1H) method. Their binding were checked by using another Y1H and luciferase (LUC) assays, indicated that TaWRKY74 bound to the TaGST1 promoter via W-box sequence. Moreover, TaWRKY74 or TaGST1 expression, GST activity, and GSH content were significantly inhibited in transiently TaWRKY74-silenced wheat plants under Cu stress. However, the contents of hydrogen peroxide (H2O2), malondialdehyde (MDA), and Cu were significantly increased. Further investigation found that transiently ectopic overexpression of TaWRKY74 increased GSH content, whereas decreased MDA content during Cu stress. Notably, exogenous application of GSH could reversed the adverse effects of transiently TaWRKY74-silenced wheat plants during Cu stress. Conclusions: These results indicated that TaWRKY74 regulated TaGST1 expression and affected GSH synthesis under Cu stress, and could be useful to ameliorate Cu toxicity for crop food safety.

Download Full-text

Absorption and Distribution of Heavy Metal in Erigeron breviscapus (Vant) Hand-Mazz

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.2364 ◽

2013 ◽

Vol 295-298 ◽

pp. 2364-2370 ◽

Cited By ~ 1

Author(s):

Hua Bin Xiong ◽

Ming Hong Chen ◽

Xin Xiang A ◽

Meng Sheng Chen ◽

Yu Cheng Chen ◽

...

Keyword(s):

Heavy Metal ◽

Metal Accumulation ◽

Plant Root ◽

Human Health Risk ◽

Heavy Metal Concentration ◽

Heavy Metal Accumulation ◽

Erigeron Breviscapus ◽

Potential Human Health Risk ◽

Potential Human Health ◽

Selection Of

Heavy metal accumulation is effect normal plant growth, and brings potential human health risk in edible and medicinal plants. Erigeron breviscapus is a famous and important traditional China medicine plant, but research of absorption and accumulation for heavy metal is very limited, however that will help the guarantee of quality and food safety as medicine, and offer cultivation guidance and selection of main medicinal parts. The results showed that in pollution-free soil four heavy metals (lead, chromium, cadmium and cuprum) are low concentration in Erigeron breviscapus, but with an increase of heavy metal concentration in soil its amount showed a rising trend in different organs. Lead and chromium enriched mainly by plant root, but cadmium and cuprum easily transfer into above-ground parts because of strongly translocation ability themselves. Therefore cultivate of medicine materials must select pollution-free soil to avoid direct and indirect danger from heavy metal pollution.

Download Full-text