# Biosorption of Pb(II) Using Coffee Pulp as a Sustainable Alternative for Wastewater Treatment
## 1 Introduction
Due to this aspect, the EPI requires the collection of data in the areas of water resources, sustainable agriculture, waste management, threats to biodiversity and heavy metals--different from lead--that are in the list of the thirteen mentioned by the WHO [2]. According to the high ratings and the positions assigned by the mentioned indicator, among the reasons that justify these ratings in countries such as Finland, Germany, Japan and Sweden, with a score close to or equal to 100, are that they had adequately managed pollution by this metal, which can be attributed to the progressive elimination of gasoline with lead since the 1970s, and to the strengthening of public health surveillance mechanisms, as well as policies for Pb waste incineration facilities in the late 1990s and the banning of paints containing this pollutant [5,6]. In contrast to the world leaders cited for this indicator, countries such as Egypt, Nepal, Honduras, India, Sudan, Bangladesh, Pakistan, Haiti and Afghanistan obtained the lowest ratings, because these countries are in the process of mitigating the Pb exposure and/or have very weak or even non-existent chemical safety standards and regulations, as well as detailed risk investigations or prevention strategies in response to lead poisoning [2]. It is noted that this highly toxic heavy metal (lead)--with atomic number 82, atomic density 11.35 g\(\cdot\)mL\({}^{-1}\), atomic mass 207.2 g\(\cdot\)mol\({}^{-1}\) and oxidation states 2+ and 4+--is the only metal that appears in the EPI, as previously mentioned, contemplating the global epidemiological studies of the Global Burden of Disease Study (GBD) Health Assessment, since it is considered one of the most important environmental threats to the health of pregnant women and children [2]. [PERSON] et al. [3] claim that the WHO estimated in 2012 that lead was responsible for causing mental retardation of a mild to moderate degree in 0.6 million children per year, given that they can absorb four to five times more of this contaminant than adults, since the brain and the nervous system (NS) of children are more sensitive to the harmful effects of this contaminant [7]. In the case of pregnancy, Pb can be stored in the maternal bone, where it can mobilize into the bloodstream, transferring from the mother to the child. In addition, high levels of this metal can cause miscarriages, premature births and fetal malformations [8]. At the level of affectations in the bone system, Pb interferes with the function of calcium, hemoglobin synthesis and causes neurological damage, since it can persist for up to 20 years. Likewise, in the central nervous system (CNS), Pb generates paresthesia effects, pain and muscle weakness, and affects the kidneys with oliguria and albuminuria [9], while in the male reproductive system, it affects sperm motility. One of the most well-known diseases produced by the high concentration of this metal corresponds to plumblism, saturnism or lead poisoning, which can cause gastrointestinal symptoms, encephalopathy  
Figure 1: Environmental Performance Index (EPI) for Pb exposure in the category of heavy metals within the environmental health objective [2]. (Measure of lead exposure using age-standardized number of disability-adjusted life years (DALY) lost per 100,000 people due to this risk. Data on DALY rates of lead exposure come from the Health Metrics Institute and Assessment of the Global Burden of Disease Study (GBD), which is the most comprehensive global epidemiological study of lead exposure to date.) and renal failure [10]. Regarding industrial activities and the importance of this metal, [PERSON] and Granada [11] state that Pb is used in the manufacture of car batteries, gasoline additives, wire coating, production of pipes and cisterns, manufacture of pigments for paints and varnishes, manufacture of crystals, glazing of ceramics, welding of cans and in cosmetics, toys and antiseptics.