Despite high AR exposure levels , both studies reported very low numbers of animals dying primarily from AR exposure. Nevertheless, AR poisoning may significant impact mortality rates in Californian fisher populations , with increasing prevalence from 2007 to 2014. AR contamination is not limited to mammals. It was also documented in northern spotted owl and barred owl populations, likely through secondary poisoning from predation on contaminated rodents . Despite some limitations due to small sample sizes , these studies draw attention to a potential ecological threat posed by illicit cultivation methods. Far less is known about application of chemicals in legal growing operations, which vary greatly by region and country. While some ARs are illegal or heavily restricted in the United States, various other pest-control methods have been reported for cannabis . In the US, due to the crop’s federally illegal status, no commercially available pesticides have been approved for use on cannabis . In Canada, 25 pesticide and fungicide compounds have been approved for legal use on cannabis.Wang, et al. measured biogenic volatile organic compounds emitted by cannabis plants grown under conditions mimicking greenhouse cultivation. Results suggested BVOC emissions from indoor cultivated cannabis in Colorado could contribute to ozone formation and particulate matter pollution. The authors acknowledged limitations due to small sample sizes,4x8ft rolling benches sub-optimal growing conditions, and a focus on only 4 out of 620 reported cannabis strains.

In a follow-up study, Wang, et al. estimated terpene emissions and regional ozone impacts from indoor cannabis cultivation facilities in Colorado using the Comprehensive Air Quality Model. Results predicted increases in hourly ozone concentrations which may have consequences for regional air quality. This approach was limited by reliance on estimates and assumptions in the absence of data regarding emission capacity of most cannabis strains, number of plants and plant biomass. Nevertheless, preliminary findings indicated that concentrated indoor cannabis cultivation could influence ozone pollution through BVOC emissions from terpenes, particularly in areas where nitrogen oxides are not the limiting factors in ozone formation . Surface- and ground-water pollution from the cannabis industry, including from soil erosion, pesticide and fertilizer in run-off, chemical processing or waste disposal operations, is a likely risk . Nevertheless, we found no peer-reviewed study quantifying the impacts of cannabis cultivation on water quality, although current pilot projects in California are underway. We did find an academic book series and five peer-reviewed publications documenting the effects of pollution from cannabis consumption on water quality. These studies used THC-COOH concentrations in sewage systems, presumably originating from human consumption, as a proxy. Evidence of THC-COOH presence was found in both raw and biologically treated wastewater across major European cities as well as in raw wastewater in the US . Concentrations of chemical compounds derived from cannabis were lower in treated than in raw wastewater. Nevertheless, accumulation of these compounds may contribute to waterway contamination downstream from wastewater effluent discharges in urban areas, although likely to a lesser extent than other illicit drugs . While these studies primarily aim to document urban cannabis consumption, they also point towards potential contamination issues impacting downstream freshwater ecosystems.

Our current understanding of the consequences of wildlife exposure to cannabis-related chemicals remains limited. Parolini, et al. sought to bridge this gap through experimental exposure of zebra mussels to concentrations of cannabis active compounds Δ-9-THC and THC COOH. Results showed that prolonged exposure could contribute to oxidative and genetic damage in the mussels. Still, given the lack of knowledge regarding actual Δ-9-THC and THC COOH concentrations in aquatic ecosystems, and the lack of documentation of the compounds’ effects on mussels or other organisms in the wild, it is difficult to draw broader conclusions about potential environmental risks posed by exposure to active compounds in cannabis for aquatic organisms.Because there are environmental trade-offs across production methods, it is important for policy makers to consider the potential unintended consequences of policy decisions. For example, in California, stringent water-use regulations for outdoor production may incentivize cultivators to turn to alternative indoor production methods. While this shift may alleviate water-stress in sensitive ecosystems, it may also increase the carbon footprint of cannabis by encouraging energy-intensive indoor production. Identifying and understanding trade-offs within and across systems is thus important, and cannabis regulation should be comprehensive in order to prevent impacts from being displaced from one pathway to another. The emerging literature on cannabis and the environment already provides useful insights to guide policy. Still, the majority of studies reviewed here were individual case studies, mostly geographically centered in Northern California. There is a tremendous need for similar studies to be carried out across different biophysical, socioeconomic, historical and cultural contexts, both to confirm the generalizability of these results and to avoid exporting environmental problems from the developed to the developing world. We expect that continued liberalization worldwide will provide expanded geographic scope for this work for years to come, and researchers should be ready to act on this expansion.

Most of the literature reviewed here relies on observational or model-based methodologies . While these approaches provide insights, experimentation is fundamentally needed to understand basic agroecological functions and processes governing cannabis cultivation. Trials quantifying the energy footprints, water use, and nutrient requirements of different cultivation and management methods are also needed to improve the efficiency of production systems. Given increased liberalization trends, we expect to see a normalization of cannabis-related research. Scientists should be encouraged to carry out a range of experiments to bolster scientific capacity to assess the environmental impacts of an expanding cannabis sector. Additionally, as regulations around cannabis cultivation are implemented, long-term studies are needed to understand how these regulations affect cannabis cultivation practices. Cannabis cultivation may lead to additional environmental impacts, which remain scientifically undocumented to our knowledge. For instance, solid waste management of materials originating from cultivation, packaging, or other production processes, will need to be addressed. Life-cycle assessments of the cannabis sector could provide information on how to minimize such waste and more generally increase the efficiency and sustainability of cannabis production processes. Other potential areas for future research include odor pollution risks in communities where increased cannabis production has led to farms being sited near residential areas, cross pollination issues between cannabis and hemp , alternative cannabis farming or transportation efficiency. These topics, and many others, should make the study of cannabis’ environmental impacts a rich field for discovery for many years to come. Traditionally, cannabis has been cultivated remotely and at small scales. Legalization is altering this through cultivation expansion, shifts toward urban areas, and increased size of production facilities , which may in turn affect the environmental impacts of the industry. The intensification of cultivation activities at large-scale facilities may magnify negative impacts. Conversely,flood and drain table economies of scale may increase the efficiency of larger facilities which may have broader capacities to invest in sustainable production processes. Larger facilities are also less likely to be located in remote sensitive areas than historical smaller farms, but may lead to land use trade-offs with other forms of agriculture. Continued diligence by policy makers and consumers is needed to ensure that the move towards industrialization is not a move away from sustainability – and researchers must continue to document shifts in the industry and their environmental impacts. In conjunction with legalization, social and ecological certification schemes could increase environmental performance of the industry. Emerging programs such as Sun and Earth Certification or planned appellation designations in California constitute first steps in this direction. By contributing to consumer awareness and providing incentives for growers to produce in sustainable ways, these programs may pave the way for the development of a more sustainable cannabis sector. In many ways, the question of how to best produce and consume cannabis while protecting the environment echoes larger debates about the environmental impacts of agricultural production in general. Current discourse on the optimal ways to address shifts in the cannabis sector touches upon fundamental sustainability framings such as land sparing vs. land sharing, intensification vs. expansion, technology-driven agriculture vs. agroecology, the role of smallholder farmers vs. industrial-scale facilities. Policy makers working with cannabis have strong interests in developing effective regulations following legalization and are also dealing with regulatory “blank slates”. This may equip them with a novel combination of increased freedom and institutional capacity to test and evaluate the effectiveness of multiple policy approaches. Ultimately, failures and successes of environmental regulations for cannabis may lead to important lessons-learned for agriculture more broadly. This study represents original research on the manufacture of plant-made biologics and plant-made industrial products through application of analytical modeling tools in silico. The main goal of this study was to evaluate unit operations in two plant-made bio-manufacturing processes and estimate the cost of goods of the active ingredient and the impact of those costs on the cost of the final product.

A secondary but equally important goal was to compare the manufacturing cost of plant-produced AI to the cost of the same AI manufactured by predecessor technologies. Much progress has been made towards the development of manufacturing infrastructure for plant-made pharmaceuticals , which typically consist of recombinant proteins applied as vaccine antigens, therapeutic enzymes, or monoclonal antibodies. Progress has also been made in the manufacture of plant-based biologics, biochemicals, and bio-materials for industry, food, and other applications. Significant and industrially relevant advances in gene expression and bio-processing methods have been achieved during the past two decades, as reviewed in several prior studies. Yet, to date, only three PMP products have been approved by regulatory agencies for commercial sale, including an anti-caries antibody , an animal health vaccine , and a therapeutic enzyme to manage a metabolic disorder]. This relative scarcity of PMP products reflects the magnitude of the challenges in creating a new manufacturing industry. The development of the plant-based platform has slowly progressed through a multinational “labor of love” in the absence of the levels of investment originally made by the bio-pharmaceutical industry , which resulted in elevation of fermentation-based systems to their current level of dominance.Interestingly, beginning in 2009, the US Defense Advanced Research Projects Agency’s Blue Angel program made several multi-million dollar investments at various sites with the goals of accelerating the scale up of the PMP infrastructure and assessing production of relevant volumes of pandemic influenza candidate antigens as a model product to test the plant-based platform . This was a shared investment initiative, and as a result of federal and state government and private investments, the expanded PMB manufacturing capacity should now support production of at least several of the many plant-made vaccines, bio-therapeutics, bio-materials, and bio-catalysts that are under development by companies and institutions worldwide . Although capacity expansion helped companies that would manufacture their own or partnered products , these investments also helped expand capacity at PMP contract development and manufacturing organizations such as Kentucky Bio-Processing . This was important to our modeling because the decision to construct a new dedicated manufacturing facility versus contracting services from a CDMO could yield very different cost-of-goods projections. Fundamental to the commercial introduction of PMB products is the availability of an efficient plant-based manufacturing infrastructure that is at a minimum competitive with and ideally superior to traditional animal cell and microbial fermentation systems as well as to extraction from raw materials from natural sources. The cost to manufacture any product is of paramount importance to its market acceptability, availability to those who need it most, and to the profitability of the product for its manufacturer. While plant based technologies are often assumed to offer significant cost advantages relative to cell-based fermentation, such assumptions are based on the lower upstream capital investments required for plant growth, lower cost of media, no adventitious agent removal, and other factors. However, few of these studies have listed engineering process assumptions or analyzed unit operations adequately; reports such as those of Evangelista et al. and Nandi et al. are exceptions. Therefore, results of recent technoeconomic evaluations for PMP/PMB/PMIP have not been widely available in the public literature. To analyze and quantify the cost efficiency of plant based manufacturing, we chose two enzymes representing active ingredients for diverse product classes and derived for each AI the bulk product and per dose or per-unit costs.