Journal of Geochemical Exploration 176 (2017) 57–63
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Journal of Geochemical Exploration 176 (2017) 57–63 Contents lists available at ScienceDirect Journal of Geochemical Exploration journal homepage: www.elsevier.com/locate/gexplo Analysis of heavy metals in Pseudostellaria heterophylla in Baiyi Country of Wudang District Yishu Peng a,b,RongChenc,⁎, Ruidong Yang a,b a College of Resource and Environmental Engineering, Guizhou University, Guiyang, Guizhou, 550025, China b Key Laboratory of Karst Environment and Geohazard Prevention, Ministry of Education (Guizhou University), Guiyang, Guizhou, 550025, China c Mining College of Guizhou University, Guiyang, Guizhou, 550025, China article info abstract Article history: To understand the correlation between the contents of five heavy metals (including arsenic, As; cadmium, Cd; Received 11 April 2015 copper, Cu; mercury, Hg; and lead, Pb) and Pseudostellaria heterophylla quality in Baiyi Country of Wudang Dis- Revised 27 January 2016 trict, nine samples of P. heterophylla and planting soil were collected in the research area. After pre-treatment, Accepted 28 February 2016 the samples were sent to ALS Minerals–ALS Chemex (Guangzhou) Co. Ltd., for inductively coupled plasma atomic Available online 2 March 2016 emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) to determine their heavy metal contents. The average contents of the heavy metals in P. heterophylla are not higher than the Keywords: Chinese medicinal materials limited standard value (LSV) of the heavy metals, and they generally conform to quality requirements. Except Pseudostellaria heterophylla for Cd, the bioconcentration factors (BFs) of the heavy metals are not higher than 0.5, and those for Pb and As Heavy metals are especially low. Cd is slightly enriched in P. heterophylla and the other heavy metals are not. There is a signif- Bioconcentration factor icant positive correlation between the Cu and As in planting soil, a more significant positive correlation among of Enrichment factor As, Cd and Pb in P. heterophylla, and the correlations among the other elements are not significant. The levels of enrichment of As, Cd, Cu and Pb contents are very severe, minor, not enriched and moderate in planting soil, respectively. As and Pb are mainly derived from anthropogenic activities. In particular, very severe As pollution by anthropogenic sources occurs. In addition, Cd and Cu are mainly from naturally occurring sources, and Cd may be impacted by anthropogenic activities. © 2016 Published by Elsevier B.V. 1. Introduction soils of the Duero river basin, where both anthropogenic activities (mainly agriculture and industry) and natural factors may be responsi- Heavy metals generally exist in the crust, rock, soil, water, atmo- ble for their total concentrations. Chen et al. (2014a) thought that natu- sphere and biosphere, and some heavy metals in some environments ral and anthropogenic processes were the main sources of heavy metals may come from natural and anthropogenic sources. People generally in marine environments. Chen et al. (2014b) highlighted that grain size defined the heavy metals as a group of elements that has an atomic influences both elements that are mostly derived from natural sources number greater than 20 and a density higher than 5 g·cm−3 (Qadir and elements impacted by anthropogenic activities, and they proposed et al., 2014). Heavy metals are ubiquitous in the environment, and the to name some elements that are commonly used by human activities as heavy metals in the soil environment mainly result from both natural “anthropophile” elements. and anthropogenic activities (Adriano, 2001; Alloway, 2013; Aelion Heavy metals play a vital part role in the health of plants, animals et al., 2009; Bradl, 2005; Hu et al., 2013; Khan et al., 2008, 2013; and human beings, and they directly or indirectly influence the health Nagajyoti et al., 2010; Senesi et al., 2009; Siegel, 2002). Examples of nat- of plants, animals and humans. Contamination by heavy metals is an es- ural processes that produce heavy metals are weathering, erosion of sential indicator of environmental health (Chen et al., 2014a). It may not parent rocks, atmospheric deposition and volcanic activities, and exam- only affect the production and quality of crops, but it may also influence ples of anthropogenic activities that produce heavy metals are sewage the quality of the atmosphere and water bodies, and it may threaten the irrigation, addition of manures, fertilizers and pesticides (Khan et al., health of animals and human beings by the way of the food chain 2013). Qadir et al. (2014) concluded that the cadmium (Cd) in the envi- (Cheng, 2003). The accumulation of heavy metals in vegetables may ronment comes from natural and anthropogenic sources. Nanos and create a potential public health risk (Gebrekidan et al., 2013; Nagajyoti Martín (2012) investigated seven heavy metals in the agricultural et al., 2010; Pinto et al., 2015), because they are toxic to humans and plant tissues (Khan et al., 2015). Moreover, the influence of heavy metals in Pseudostellaria ⁎ Corresponding author at: Mining College, Guizhou University, Guiyang, Guizhou, 550025, China. heterophylla cannot be ignored in our daily life. P. heterophylla is vital E-mail address: [email protected] (R. Chen). to human beings, because it has many benefits and applications. http://dx.doi.org/10.1016/j.gexplo.2016.02.011 0375-6742/© 2016 Published by Elsevier B.V. 58 Y. Peng et al. / Journal of Geochemical Exploration 176 (2017) 57–63 Taizishen (P. heterophylla), which belongs to Caryophyllaceae,isalso sweating, thirst, and coughing due to dryness of the lungs (Chinese known as Haiershen (Pseudostellaria ginseng), Tongshen and so forth, Pharmacopoeia Commission, 2010). In our daily life, P. heterophylla and its scientific name is Pseudostellaria heterophylla (Miq.) Pax ex Pax has several main applications (Wu and Lin, 2004; Yan, 2008), including et Hoffm. (Xiao, 2002; Chinese Pharmacopoeia Commission, 2010). medicinal value, edible value, nutritional and healthy value, and appli- Dried P. heterophylla root is one of the most commonly-used materials cation in cosmetics. in traditional Chinese medicine. It has efficacy for replenishing qi to in- Therefore, it is necessary to carry out research on the heavy metals in vigorate the spleen and for promoting fluid production to nourish the P. heterophylla. With the improvement of living standards of people and lungs, and it is mainly used to treat symptoms such as spleen deficiency the development of society, people pay increasing amounts of attention and fatigue, inappetence, weakness after illness, qi and yin deficiency, to their health, and they are increasingly concerned for the safety of Fig. 1. Location of research area. Y. Peng et al. / Journal of Geochemical Exploration 176 (2017) 57–63 59 Table 1 Contents of heavy metals in the planting soil of the research area (mg·kg−1, except for Al: %). TR1 TR2 TR3 TR4 TR5 TR6 TR7 TR8 TR9 Minimum Maximum Average CCA SQV As 76.6 84.2 33.3 61.2 36.9 50.0 29.9 45.0 40.4 29.9 84.2 50.83 1.8 40 Cd 0.40 0.39 0.21 0.20 0.33 1.04 0.21 0.23 0.22 0.20 1.04 0.36 0.2 0.30 Cu 57.8 58.0 28.0 50.9 38.9 46.9 37.9 54.7 26.0 26.0 58.0 44.34 55 50 Pb 99.4 131.0 40.3 90.6 120.5 124.5 94.9 83.1 62.0 40.3 131.0 94.03 12.5 250 Hg ND ND ND ND ND ND ND ND ND ND ND ND 0.08 0.30 Al 10.35 9.29 7.12 9.66 8.82 9.20 8.78 9.40 6.28 6.28 10.35 8.77 8.23 NF ND means that the value was not measured. NF means that the value was not found. SQV refers to the soil quality value of grade two (Chinese Environmental Protection Agency and Chinese Technical Supervision Agency, 1995). CCA is the average abundance of chemical elements in the continental crust (Taylor, 1964). their food and drugs. At the same time, although China has played a type of subtropical monsoon climate with characteristics of a plateau vital part role in the WTO, the contamination of heavy metals in Chi- climate, such as a lack of severe cold in winter, a lack of extreme heat nese medicinal materials may hinder it from being used globally. in summer, rain in the warm season, and clearly perpendicular gradi- Chinese Pharmacopoeia Commission (2013) issued a draft standard ents in climate characteristics. The area has an annual average rainfall of the heavy metals and other limited indexes in Chinese medicinal ranging from 1 179.8 to 1 271 mm, an annual average relative humidity materials to further enhance their quality and safety. Traditional Chi- of 78%, an annual average temperature of 14.6 °C, an annual extreme nese medicine (TCM) plays an important role in the health care sys- maximum temperature of 35.1 °C and a minimum temperature of tems in many parts of the world (Ueng et al., 1997). We should pay −7.3 °C. The area mainly consists of mountainous territory, with higher attention to the heavy metals in the medicines and their influence. elevations in the north and lower elevations in the south. The slopes are Heavy metal poisoning had been repeatedly associated with TCM in gentle in the west and steeper in the east, and its elevation ranges from some reports or cases (Ernst and Coon, 2001). Through evidence 872 to 1659 m. Thus, the area meets the growth requirements for many from various countries, Ernst (2002) implied that toxic heavy metals Chinese medicinal materials. There are many landform types in the area, and undeclared prescription drugs in Asian herbal medicines might such as mountains and hills, valleys, intermontane basin and low-lying constitute a serious health problem.