Metal concentrations (As, Cd, Pb, Cr, Ba, Co, Ni, Cu, and Zn) in conventional and organic produce were assessed, specifically, five most-consumed vegetables from the US including potato, lettuce, tomato, carrot and onion. They were from four representative supermarkets in a college town in Florida. All vegetables contained detectable metals, while As, Cd, Pb, Cr, and Ba are toxic metals, Co, Ni, Cu, and Zn are nutrients for humans. The mean concentrations of As, Cd, Pb, Cr and Ba in five vegetables were 7.86, 9.17, 12.1, 44.8 and 410 μg/kg for organic produce, slightly lower than conventional produce at 7.29, 15.3, 17.9, 46.3 and 423 μg/kg. The mean concentrations of Co, Ni, Cu, and Zn in five vegetables were 3.86, 58.5, 632, and 2528 μg/kg for organic produce, comparable to conventional produce at 5.94, 68.2, 577, and 2354 μg/kg. For toxic metals, the order followed tomato < lettuce < onion < carrot < potato, with root vegetables being the highest. All metals in vegetables were lower than the allowable concentrations by FAO/WHO. Health risks associated with vegetable consumption based on daily intake and non-carcinogenic risk based on hazard quotient were lower than allowable limits. For the five most-consumed vegetables in the US, metal contents in conventional produce were slightly greater than organic produce, especially for Cd and Pb.

Wastewater pollution results in detrimental effects on ecosystems and poses human health hazards. As the human population and urbanization rates increase, so do abiotic and biotic contaminants such as Escherichia coli within natural waterways. For example, the Chicago River has been degraded by contaminants and untreated sewage from city occupants since the late 1700s. Surprisingly, water treatment of the Chicago River has not met EPA freshwater river standards for some time, creating a need for remediation alternatives. Such an alternative is mycoremediation, where fungi are used to degrade and remove water contaminants. To explore this alternative for bioremediation of contaminated waterways, this two-part study focused on the feasibility and time efficiency of mycoremediation of polluted waters through mycofiltration. In the lab-based experiment, known amounts of E. coli–inoculated water were processed through organic wheat straw with mycelia of Pleurotus ostreatus (oyster mushroom) to assess if these fungi were capable of E. coli removal and at what rates. The second part of the study replicated the lab-based experiment with water samples from the Chicago River. Results showed that mycelia treatments were able to remove significant amounts of E. coli in lab- and field-sampling-based settings (99.25% and 99.74% over 96 h respectively), and did so at higher rates within the initial 48 h. With a substantial E. coli reduction by fungal mycelia from initial colony counts over 96 h, our study demonstrated that mycoremediation may be a feasible and possible option for natural contaminant remediation.

Levels of antibiotic resistance genes (ARGs) and the fractions of antibiotic resistant bacteria (ARB) among culturable heterotrophic bacteria were compared in outdoor air near conventional (n = 3) and organic (n = 3) cattle rearing facilities. DNA extracts from filters taken from 18 locations were analyzed by quantitative polymerase chain reaction (qPCR) for five ARGs. At the reference (non-agricultural) site, all genes were below detection. ARGs sul1, bla SHV, erm(B), and bla TEM were more frequently detected and at higher levels (up to 870 copies m⁻³ for bla SHV and 750 copies m⁻³ for sul1) near conventional farms compared to organic locations while the opposite was observed for erm(F) (up to 210 copies m⁻³). Isolates of airborne heterotrophic bacteria (n = 1295) collected from the sites were tested for growth in the presence of six antibiotics. By disk diffusion on a subset of isolates, the fractions of ARB were higher for conventional sites compared to organic farms for penicillin (0.9 versus 0.63), cloxacillin (0.74 versus 0.23), cefoperazone (0.58 versus 0.14), and sulfamethazine (0.50 versus 0.33) for isolates on nutrient agar. All isolates’ ΔA600ₚᵣₑₛ/ΔA600ₐbₛ were measured for each of the six tested antibiotics; isolates from farms downwind of organic sites had a lower average ΔA600ₚᵣₑₛ/ΔA600ₐbₛ for most antibiotics. In general, all three analyses used to indicate microbial resistance to antibiotics showed increases in air samples nearby conventional versus organic cattle rearing facilities. Regular surveillance of airborne ARB and ARGs near conventional and organic beef cattle farms is suggested.

An increasing amount of evidence suggests that phthalic acid esters (PAE), polychlorinated biphenyls (PCB), polybrominated diphenyl ethers (PBDE), and organochlorine pesticides (OCP) are related to mutagenic, carcinogenic, and endocrine disruptor effects (EDCs). These lipophilic compounds are highly resistant to breakdown processes, and consequently remain in the environment, followed by uptake into the food chain. Human exposure to lipophilic compounds results from the consumption of food containing EDCs, mainly foodstuffs of animal origin with a high fat content, since these contaminants accumulate in fatty tissues. Foodstuffs in which EDCs can accumulate include meat, fish, eggs, and milk. We investigated the contamination in edible eggs to determine whether relative differences in the contaminants’ residue levels appeared in three types of egg production (i.e., battery, free-range, and organic). The results showed that PAEs, especially dimethyl phthalate contamination, was the most abundant in the battery eggs, and the PCBs, PBDEs, and OCPs were the most abundant in the free-range eggs. The eggs were contaminated by more than one chemical, and as many as five contaminants (PCB180, PBDE47, dimethyl phthalate, diethyl phthalate, and di-n-butyl phthalate in battery eggs, and PCB138, PCB153, PCB180, diethyl phthalate, and di-2-ethylhexyl phthalate in organic eggs) were detected in the same egg. However, none of the chemicals detected were at the maximum limit of acceptable risk.

Agricultural ecological compensation has drawn an increasingly broad range of interest since early 1990s. In recent years, the volume of the literature grows rapidly. As a result, a systematic review of the diverse research field and its current trends becomes essential. This paper surveys the literature of agricultural ecological compensation between 1990 and 2016. Specifically, by employing CiteSpace information visualization software, we firstly identified the research hotspots and evolution path and then illustrated the frontier and developing trend of the domain in core and broader perspectives. It is found that the focus of the academic community has always been researches on the theoretical policy and application of the payment for agro-ecosystem services, agricultural ecological compensation based on contingent valuation method, and ecological compensation of farmland landscape and organic food production as well as willingness to accept/pay for land use and ecological protection. Meanwhile, we also found that, in recent years, qualitative research has received more and more attention in the field of agricultural ecological compensation, since global warming, agricultural carbon emissions, and other emerging environmental issues have aroused widespread concern of the people around the world. Moreover, we believed that more and more scholars will employ case study methodology to analyze agricultural ecological compensation in specific systems, regions, or circumstances in the future.

The application of manure-based commercial organic fertilizers (COFs) is becoming increasingly extensive because of the expanding market for organic food. The present study examined the effects of repeated applications of chicken or swine manure-based COFs on the fate of antibiotics and antibiotic resistance genes (ARGs) in soil by conducting a soil microcosm experiment. Application of COFs significantly increased antibiotics residues, as well as the relative abundance of ARGs and the integrase gene of class 1 integrons (intΙ1) in soil. Two months after each application, antibiotics and ARGs dissipated in amended soils, but they still remained at an elevated level, compared with the control. And, the accumulation of antibiotics was found due to repeated COF applications. However, the relative abundance of ARGs in most COF-amended soils did not differ significantly between the first application and the repeated application. The results imply that 2 months are not sufficient for ARGs to approach background levels, and that animal manure must be treated more effectively prior to using it in agriculture ecosystems.

The concepts of the cities we know nowadays, and which we are accustomed to, change at a very rapid pace. The philosophy of their design is also changing. It will base on new standards, entering a completely different, futuristic dimension. This stage is related to changes in the perception of space, location and lack of belonging to definite, national or cultural structures. Cities of the future are cities primarily intelligent, zero-energetic, zero-waste, environmentally sustainable, self-sufficient in terms of both organic food production and symbiosis between the environment and industry. New cities will be able to have new organisational structures—either city states, or, apolitical, jigsaw-like structures that can change their position—like in the case of the city of Artisanopolis, designed as a floating city, close to the land, reminiscent of the legendary Atlantis. This paper is focused on the main issues connected with problems of the contemporary city planning. The purpose of the research was to identify existing technological solutions, whose aim is to use solar energy and urban greenery. The studies were based on literature related to future city development issues and futuristic projects of the architects and city planners. In the paper, the following issues have been verified: futuristic cities and districts, and original bionic buildings, both residential and industrial. The results of the analysis have been presented in a tabular form.

Plastics are widely used in the production of short-life products, which are discarded producing an accumulation of these materials and problems due to their persistence in the environment and waste management systems. Degradable plastics (compostable, oxodegradable) have been presented as an alternative to decrease the negative effect of plastic waste. In this research, the feasibility of degrading a commercially available compostable film and oxodegradable polyethylene, with and without previous abiotic oxidation, is assessed in a home composting system. Reactors (200 L) were used to degrade the plastic films along with a mixture of organic food waste (50 %), mulch (25 %), and dry leaves (25 %), amended with yeast and a solution of brown sugar to increase the speed of the process. The presence of the plastic film did not affect the composting process, which showed an initial increase in temperature and typical profiles for moisture content, pH, with a final C/N of 17.4. After 57 days, the compostable plastic has decreased its mechanical properties in more than 90 %, while the oxodegradable film did not show significant degradation if it was not previously degraded by UV radiation. The use of these plastics should be assessed against the prevailing waste management system in each city or country. In the case of Mexico, which lacks the infrastructure for industrial composting, home composting could be an option to degrade compostable plastics along organic waste. However, more testing is needed in order to set the optimal parameters of the process.