Risk assessment for safety of soils and vegetables around a lead/zinc mine

Concentrations of heavy metals (Pb, Zn, Cd, Cu) were determined in soils and vegetables (chrysanthemum, spinach and four cultivars of Chinese cabbage from the area adjacent to a Pb/Zn mine in Shaoxing, Zhejiang province, China, and compared with the Chinese National Standards for Soil Environmental Quality. The accumulation of heavy metals in cabbage cv. Siyuegreen was investigated at different distances from the center of the mine. The vegetable plantation soils were polluted with Pb, Cd, Cu and Zn, especially by Pb and Cd. The levels of Pb and Cd were 20 and 30 times higher than the permitted standards, indicating that this Pb/Zn mining area is unsuitable for agricultural use. Chinese cabbage, chrysanthemum and spinach had different enrichment coefficients. The enrichment coefficient of Cd from soil to roots of chrysanthemum was >80% and from roots to leaves of cabbage cv. Shanghaigreen was >120%. These vegetables were polluted by heavy metals and could not be regarded as safe for human consumption. Environmental accumulation of heavy metals in the vegetable plantation soils was proportional to heavy metal accumulation in vegetables and both were inversely proportional to the distance from the lead/zinc mine.     

Biodegradability of Epoxidized Soybean Oil Based Thermosets in Compost Soil Environment

In this study, bio-thermoset from epoxidized soybean oil (ESO) was prepared in the presence of methylhexahydrophthalic anhydride curing agent and 2-ethyl-4-methylimidazole catalyst. The crosslink densities of the synthesized ESO are ranged from 0.109 × 10^?3 to 0.308 × 10^?3 mol/cm³. The ESO bio-thermosets were exposed to the soil-burial test for 8 months. Weight change and morphology of the degraded ESO specimens were assessed. It was found that the weight loss of ESO was governed by the materials compositions, crosslink density and the soil-burial exposure time. The 3 mm thickness ESO bio-thermosets with crosslink density of 0.109 × 10^?3 mol/cm³ had fully biodegraded after soil-burial for 6 months. In addition, 16S rDNA sequencing was carried out to identify the soil microorganisms. It was suggested that Comamonas sp., Bacillus sp., Streptomyces sp. and Acinetobacter sp. are the possible soil microbes that degrade the ESO bio-thermosets in the compost soil environment.     

IFTCIP: An Integrated Optimization Model for Environmental Management under Uncertainty

In this study, an interval-fuzzy two-stage chance-constrained integer programming (IFTCIP) method is developed for supporting environmental management under uncertainty. The IFTCIP improves upon the existing interval, fuzzy, and two-stage programming approaches by allowing uncertainties expressed as probability distributions, fuzzy sets, and discrete intervals to be directly incorporated within a general mixed integer linear programming framework. It has advantages in uncertainty reflection, policy investigation, risk assessment, and capacity-expansion analysis in comparison to the other optimization methods. Moreover, it can help examine the risk of violating system constraints and the associated consequences. The developed method is applied to the planning for facility expansion and waste-flow allocation within a municipal solid waste management system. Violations of capacity constraints are allowed under a range of significance levels, which reflects tradeoffs between the system cost and the constraint-violation risk. The results indicate that reasonable solutions for both binary and continuous variables have been generated under different risk levels. They are useful for generating desired decision alternatives with minimized system cost and constraint-violation risk under various environmental, economic, and system-reliability conditions. Generally, willingness to take a higher risk of constraint violation will guarantee a lower system cost; a strong desire to acquire a lower risk will run into a higher system cost.     

Risk assessment and distribution of soil Pb in Guangdong, China

In this study, the spatial distributions of soil lead (Pb) concentration in three horizontal soils in Guangdong, China, were surveyed and analyzed using geostatistics and geography information systems (GIS). Findings indicated that the Pb geometric mean concentration of 23.3 mg/kg in surface soils was found to be higher than those in global soils, which ranged from 2.3–235 mg/kg. In addition, the Pb geometric mean concentrations from A- to C-horizon were found to be 23.3, 27.2, and 28.6 mg/kg, respectively. The classification of a soil Pb environmental risk in an area was likewise presented based on the different levels of environmental quality of Pb and was done by GIS technology. Accordingly, there is a higher local concentration of Pb in the surrounding areas of Guangzhou where there is higher population density and in the north of Guangdong, which is a historic mining area. The results obtained by the environmental risk assessment reveal that about 46% of total surveyed area was above the background value, that is, 2.7% of the total area was at risk of pollution.     

Prenatal diagnosis of the fragile X using thymidine induction

Eleven pregnancies in ten patients at risk for the fragile X were monitored by amniocentesis or chorion villus biopsy and induction of the fragile site using thymidine, methotrexate and FUdR. Three female fetuses and one male fetus were found to have the fragile X. The results obtained using thymidine induction were superior to those using methotrexate induction and probably better than those obtained using FUdR induction.     

Hydrogeochemical data as a tool for exploration and mapping: a case study from part of Afikpo Basin southeastern Nigeria

Fourteen (14) characters from six (6) water samples collected from springs, ponds, and streams located in Lower Cretaceous sedimentary area of Afikpo Basin have been analyzed. These include pH, turbidity, conductivity, total dissolved solid, hardness, Fe²⁺, Ca²⁺, Mg²⁺, K⁺, NO₃ ^?, Cl^?, SO₄ ^2?, and Na⁺. These sediments, which are Turonian and Coniacian in age, are subdivided into two by a basic rock dyke. Results of the analyses show clearly that the Turonian sediments, intruded by dolerite, have net Fe²⁺, HCO₃ ^?, Ca²⁺, Mg²⁺, Mn²⁺, Cl^?, and SO₄ ^2? concentration while those from the younger Coniacian sediment have net higher amounts of K⁺, Na⁺, and Mn²⁺. The overriding mafic minerals in the basic intrusive rock possibly led to higher leaching into ground water system near it. On the other hand, the presence of feldsparthic to kaolinitic sands of the younger Coniacian units led to higher K⁺ and Na⁺ matter in the water from these zones. The formations dip away from the older sediments. Concentrations of these characters are within acceptable drinking water standards by World Health Organization but noticeable anomalous zones for Fe²⁺, Mg²⁺, and Ca²⁺ are zones of basic rock suites. Areas with greater Na⁺ and K⁺ are traceable to sandy units. It is thus concluded that more analysis of surface, subsurface, and pond water samples can be utilized for minerals search and geological mapping. At this stage, it forms a veritable reconnaissance tool.     

Development of eco-friendly bioplastic like PHB by distillery effluent microorganisms

During screening for poly-β-hydroxybutyrate (PHB) producing bacteria from distillery effluent sample, six out of 30 isolates comprising of three strains of Alcaligenes sp., two strains of Bacillus sp., and one strain of Pseudomonas sp. were found to accumulate varying levels of intracellular PHB. Amongst the various isolates, Alcaligenes sp. RZS4 was found as the potent PHB-producing organism, accumulating higher amounts of PHB. PHB productivity was further enhanced in the presence of oxygen, nitrogen-limiting conditions, and cloning of PHB synthesizing genes of Alcaligenes sp. RZS 4 into Escherichia coli. A twofold increase in PHB yield was obtained from recombinant E. coli vis-à-vis Alcaligenes sp.; the recombinant E. coli accumulated more PHB in NDMM, produced good amount of PHB in a single-stage cultivation process under both nutrient-rich and nutrient-deficient conditions. Extraction of PHB with acetone–alcohol (1:1) was found as suitable method for optimum extraction of PHB as this mixture selectively extracted PHB without affecting the non-PHB cell mass. PHB extract from recombinant E. coli showed the presence of C–H, =O stretching, =C–H deformation, =C–H, =CH, and =C–O functional groups characteristic of PHB.     

Fuel Oil Additives for Controlling Air Contaminant Emissions

An addition of additives to fuel oils prior to combustion is one way of reducing combustible contaminant emissions to the outer air. Reported test results show that some additives improve, moderately, the combustive properties of fuel oils. Combustion is also improved but to a lesser degree, in boiler systems that are deficient in operation and design. Being combustible, polynuclear hydrocarbons emissions would be reduced by use of additives. Other types of additives to reduce slagging and inhibit corrosion from combustion of fuel oils are also available. The cost of using additives is low. Improved additives are required, especially ones to better combustion in the deficient boiler systems. These can be found by research and literature surveys. Their effectiveness and nontoxicity would be confirmed by laboratory and field testing.     

A comprehensive method for aeolian particle granulometry and micromorphology analyses

The aim of this study was to use a new approach to investigate aeolian particle granulometry and micromorphology. Taking total aeolian deposition into account, we used parameters such as, particle area, perimeter, shape analysis for particle roughness (area/perimeter) and elongation (long/short axis). These parameters were analyzed on temporal and spatial scales at four study sites in the eastern Negev Desert, Israel. The total collection of particles was sorted into three size groups based on particle area to facilitate comparison. The classic definition of particle size (equating particle length with particle diameter) produced relatively small variations among the three size classes (25-38.6%). Our proposed comprehensive method demonstrated significant variation among the three size classes (13.9-60.8%), e.g. the classic method placed 36.4% of the particles in size class two while the new method placed 60.8% of the particles in this size class; the differences were even more significant regarding size class 3 (38.6% vs. 13.9%, respectively). The classic method did not facilitate investigation of particle roughness and elongation. With this new approach, it was possible to clearly define the particles by size class, based on these characteristics. With roughness, the variation among size classes 2 and 3 was about 27%. With elongation, the variation among size classes two and three was about 21%. Applying similar investigation method to study the aeolian particle granulometry and micromorphology can better facilitate more detailed calculation of particle size distribution, roughness and elongation.     

Dust Storms are an Indication of an Unhealthy Environment in East Asia

Dust storms frequently occur in Mongolia and in northern China. Each year there are 30 to 120 dusty days in source regions of Mongolia and 14–20 dusty days on the Korean Peninsula. Intense sand storms and associated dust falls produce environmental impacts in East Asia. This paper discusses the environmental degradation in Mongolia and the social, economic and atmospheric impacts of dust storms in the sink area. The impact of dust storms on environmental compartments as well as their direct and indirect consequences to basic resources like water and energy demand and supply is explained. Governments are encouraged to take appropriate action in specified regions. For monitoring dust storms there is a need for international cooperation to combat growing environmental and human security concerns.