Cultured Meat Safety Research Priorities: Regulatory and Governmental Perspectives

As with every new technology, safety demonstration is a critical component of bringing products to market and gaining public acceptance for cultured meat and seafood. This manuscript develops research priorities from the findings of a series of interviews and workshops with governmental scientists and regulators from food safety agencies in fifteen jurisdictions globally. The interviews and workshops aimed to identify the key safety questions and priority areas of research. Participants raised questions about which aspects of cultured meat and seafood production are novel, and the implications of the paucity of public information on the topic. Novel parameters and targets may require the development of new analytical methods or adaptation and validation of existing ones, including for a diversity of product types and processes. Participants emphasized that data sharing of these efforts would be valuable, similar to those already developed and used in the food and pharmaceutical fields. Contributions to such databases from the private and public sectors would speed general understanding as well as efforts to make evaluations more efficient. In turn, these resources, combined with transparent risk assessment, will be critical elements of building consumer trust in cultured meat and seafood products.

Food safety considerations and research priorities for the cultured meat and seafood industry

Cell-cultured meat and seafood offer a sustainable opportunity to meet the world's increasing demand for protein in a climate-changed world. A responsible, data-driven approach to assess and demonstrate safety of cell-cultured meat and seafood can support consumer acceptance and help fully realize the potential of these products. As an initial step toward a thorough demonstration of safety, this review identifies hazards that could be introduced during manufacturing, evaluates applicability of existing safety assessment approaches, and highlights research priorities that could support safe commercialization. Input was gathered from members of the cultured meat and seafood industry, researchers, regulators, and food safety experts. A series of workshops were held with 87 industry representatives and researchers to create a modular manufacturing process diagram, which served as a framework to identify potential chemical and biological hazards along the steps of the manufacturing process that could affect the safety of a final food product. Interviews and feedback on draft documents validated the process diagram and supported hazard identification and evaluation of applicable safety methods. Most hazards are not expected to be novel; therefore, safety assessment methods from a range of fields, such as conventional and novel foods, foods produced from biotechnology, pharmaceuticals, and so forth, are likely to be applicable. However, additional assessment of novel inputs or products with significant differences from existing foods may be necessary. Further research on the safety of the inputs and associated residues, potential for contamination, and development of standardized safety assessment approaches (particularly animal-free methods) is recommended.

Commentary: Revisiting nanoparticle-assay interference: There's plenty of room at the bottom for misinterpretation

Engineered nanomaterials (ENMs) are a diverse class of materials whose distinct properties make them desirable in a multitude of applications. The proliferation of nanotoxicology research has improved our understanding of ENM toxicity, but an under appreciation for their potential to interfere with biochemical assays has hampered progress in the field. The physicochemical properties of ENMs can promote their interaction with membranes or biomacromolecules (e.g. proteins, genomic material). This can influence the activity of enzymes used as biomarkers or as reagents in biochemical assay protocols, bind indicator dyes in cytotoxicity tests, and/or interfere with the cellular mechanisms controlling the uptake of such dyes. The spectral characteristics of some ENMs can cause interference with common assay chromophores, fluorophores, and radioisotope scintillation cocktails. Finally, the inherent chemical reactivity of some ENMs can short circuit assay mechanisms by directly oxidizing or reducing indicator dyes. These processes affect data quality and may lead to significant misinterpretations regarding ENM safety. We provide an overview of some ENM properties that facilitate assay interference, examples of interference and the erroneous conclusions that may result from it, and a number of general and specific recommendations for validating cellular and biochemical assay protocols in nanotoxicology studies.

Fluorescently Labeled Cellulose Nanofibers for Environmental Health and Safety Studies

An optimal methodology for locating and tracking cellulose nanofibers (CNFs) in vitro and in vivo is crucial to evaluate the environmental health and safety properties of these nanomaterials. Here, we report the use of a new boron-dipyrromethene (BODIPY) reactive fluorescent probe, meso-DichlorotriazineEthyl BODIPY (mDTEB), tailor-made for labeling CNFs used in simulated or in vivo ingestion exposure studies. Time-correlated single photon counting (TCSPC) fluorescence lifetime imaging microscopy (FLIM) was used to confirm covalent attachment and purity of mDTEB-labeled CNFs. The photoluminescence properties of mDTEB-labeled CNFs, characterized using fluorescence spectroscopy, include excellent stability over a wide pH range (pH2 to pH10) and high quantum yield, which provides detection at low (μM) concentrations. FLIM analysis also showed that lignin-like impurities present on the CNF reduce the fluorescence of the mDTEB-labeled CNF, via quenching. Therefore, the chemical composition and the methods of CNF production affect subsequent studies. An in vitro triculture, small intestinal, epithelial model was used to assess the toxicity of ingested mDTEB-labeled CNFs. Zebrafish (Danio rerio) were used to assess in vivo environmental toxicity studies. No cytotoxicity was observed for CNFs, or mDTEB-labeled CNFs, either in the triculture cells or in the zebrafish embryos.

Physical, chemical, and toxicological characterization of sulfated cellulose nanocrystals for food-related applications using in vivo and in vitro strategies

Cellulose nanocrystals (CNCs) are a next-generation cellulose product with many unique properties including applications in the food industry as a food additive, food coating, and in food-contact packaging material. While CNC is anticipated to be safe due to its similarity to the many forms of cellulose currently used as food additives, special consideration is given to it as it is the first manufactured form of cellulose that is nanoscale in both length and width. A proactive approach to safety has been adopted by manufacturers to demonstrate CNC safety toward responsible commercialization. As part of the safety demonstration, in vivo and in vitro testing strategies were commissioned side-by-side with conventional cellulose, which has been safely used in food for decades. Testing included a 90-day rodent feeding study as well as additional physical, chemical, and biological studies in vitro that follow European Food Safety Authority (EFSA) guidance to demonstrate the safe use of novel food ingredients. The strategy includes assessment of neat materials side-by-side with simulated digestion, mimicking conditions that occur along the gastrointestinal tract as well as intracellularly. An intestinal co-culture model examined any potential toxicological effects from exposure to either pristine or digested forms of CNC including cytotoxicity, metabolic activity, membrane permeability, oxidative stress, and proinflammatory responses. None of the studies demonstrated any toxicity via oral or simulated oral exposure. These studies demonstrate that CNC produced by InnoTech Alberta is similarly safe by ingestion as conventional cellulose with a no-observed-adverse-effect level of 2085.3 (males) and 2682.8 (females) mg/kg/day.

Physical, chemical, and toxicological characterization of fibrillated forms of cellulose using an in vitro gastrointestinal digestion and co-culture model

Fibrillated cellulose is a next-generation material in development for a variety of applications, including use in food and food-contact materials. An alternative testing strategy including simulated digestion was developed to compare the physical, chemical, and biological characteristics of seven different types of fibrillated cellulose, following European Food Safety Authority guidance. Fibrillated forms were compared to a conventional form of cellulose which has been used in food for over 85 years and has Generally Recognized as safe regulatory status in the USA. The physical and chemical characterization of fibrillated celluloses demonstrate that these materials are similar physically and chemically, which composed of the same fundamental molecular structure and exhibit similar morphology, size, size distribution, surface charge, and low levels of impurities. Simulated gastrointestinal and lysosomal digestions demonstrate that these physical and chemical similarities remain following exposure to conditions that mimic the gastrointestinal tract or intracellular lysosomes. A toxicological investigation with an advanced intestinal co-culture model found that exposure to each of the fibrillated and conventional forms of cellulose, in either the pristine or digested form at 0.4% by weight, showed no adverse toxicological effects including cytotoxicity, barrier integrity, oxidative stress, or inflammation. The results demonstrate the physical, chemical, and biological similarities of these materials and provide substantive evidence to support their grouping and ability to read-across data as part of a food safety demonstration.

A 90-day dietary study with fibrillated cellulose in Sprague-Dawley rats

Novel forms of fibrillated cellulose offer improved attributes for use in foods. Conventional cellulose and many of its derivatives are already widely used as food additives and are authorized as safe for use in foods in many countries. However, novel forms have not yet been thoroughly investigated using standardized testing methods. This study assesses the 90-day dietary toxicity of fibrillated cellulose, as compared to a conventional cellulose, Solka Floc. Sprague Dawley rats were fed 2 %, 3 %, or 4 % fibrillated cellulose for 90 consecutive days, and parallel Solka Floc groups were used as controls. Survival, clinical observations, body weight, food consumption, ophthalmologic evaluations, hematology, serum chemistry, urinalysis, post-mortem anatomic pathology, and histopathology were monitored and performed. No adverse observations were noted in relation to the administration of fibrillated cellulose. Under the conditions of this study and based on the toxicological endpoints evaluated, the no-observed-adverse-effect level (NOAEL) for fibrillated cellulose was 2194.2 mg/kg/day (males) and 2666.6 mg/kg/day (females), corresponding to the highest dose tested (4 %) for male and female Sprague Dawley rats. These results demonstrate that fibrillated cellulose behaves similarly to conventional cellulose and raises no safety concerns when used as a food ingredient at these concentrations.

HIV care cost in England: a cross-sectional analysis of antiretroviral treatment and the impact of generic introduction

OBJECTIVES

Reliable and timely HIV care cost estimates are important for policy option appraisals of HIV treatment and prevention strategies. As HIV clinical management and outcomes have changed, we aimed to update profiles of antiretroviral (ARV) usage pattern, patent/market exclusivity details and management costs in adults (≥ 18 years old) accessing HIV specialist care in England.

METHODS

The data reported quarterly to the HIV and AIDS Reporting System in England was used to identify ARV usage pattern, and were combined with British National Formulary (BNF) prices, non-ARV care costs and patent/market exclusivity information to generate average survival-adjusted lifetime care costs. The cumulative budget impact from 2018 to the year in which all current ARVs were expected to lose market exclusivity was calculated for a hypothetical 85 000 (± 5000) person cohort, which provided an illustration of potential financial savings afforded by bioequivalent generic switches. Price scenarios explored BNF70 (September 2015) prices and generics at 10/20/30/50% of proprietary prices. The analyses took National Health Service (NHS) England's perspective (as the payer), and results are presented in 2016/2017 British pounds.

RESULTS

By 2033, most currently available ARVs would lose market exclusivity; that is, generics could be available. Average per person lifetime HIV cost was ~£200 000 (3.5% annual discount) or ~£400 000 (undiscounted), reducing to ~£70 000 (3.5% annual discount; ~£120 000 undiscounted) with the use of generics (assuming that generics cost 10% of proprietary prices). The cumulative budget to cover 85 000 (± 5000) persons for 16 years (2018-2033) was £10.5 (± 0.6) billion, reducing to £3.6 (± 0.2) billion with the use of generics.

CONCLUSIONS

HIV management costs are high but financial efficiency could be improved by optimizing generic use for treatment and prevention to mitigate the high cost of lifelong HIV treatment. Earlier implementation of generics as they become available offers the potential to maximize the scale of the financial savings.

Risk Analysis of Cellulose Nanomaterials by Inhalation: Current State of Science

Cellulose nanomaterials (CNs) are emerging advanced materials with many unique properties and growing commercial significance. A life-cycle risk assessment and environmental health and safety roadmap identified potential risks from inhalation of powdered CNs in the workplace as a key gap in our understanding of safety and recommended addressing this data gap to advance the safe and successful commercialization of these materials. Here, we (i) summarize the currently available published literature for its contribution to our current understanding of CN inhalation hazard and (ii) evaluate the quality of the studies for risk assessment purposes using published study evaluation tools for nanomaterials to assess the weight of evidence provided. Our analysis found that the quality of the available studies is generally inadequate for risk assessment purposes but is improving over time. There have been some advances in knowledge about the effects of short-term inhalation exposures of CN. The most recent in vivo studies suggest that short-term exposure to CNs results in transient inflammation, similarly to other poorly soluble, low toxicity dusts such as conventional cellulose, but is markedly different from fibers with known toxicity such as certain types of multiwalled carbon nanotubes or asbestos. However, several data gaps remain, and there is still a lack of understanding of the effects from long-term, low-dose exposures that represent realistic workplace conditions, essential for a quantitative assessment of potential health risk. Therefore, taking precautions when handling dry forms of CNs to avoid dust inhalation exposure is warranted.

Current characterization methods for cellulose nanomaterials

A new family of materials comprised of cellulose, cellulose nanomaterials (CNMs), having properties and functionalities distinct from molecular cellulose and wood pulp, is being developed for applications that were once thought impossible for cellulosic materials. Commercialization, paralleled by research in this field, is fueled by the unique combination of characteristics, such as high on-axis stiffness, sustainability, scalability, and mechanical reinforcement of a wide variety of materials, leading to their utility across a broad spectrum of high-performance material applications. However, with this exponential growth in interest/activity, the development of measurement protocols necessary for consistent, reliable and accurate materials characterization has been outpaced. These protocols, developed in the broader research community, are critical for the advancement in understanding, process optimization, and utilization of CNMs in materials development. This review establishes detailed best practices, methods and techniques for characterizing CNM particle morphology, surface chemistry, surface charge, purity, crystallinity, rheological properties, mechanical properties, and toxicity for two distinct forms of CNMs: cellulose nanocrystals and cellulose nanofibrils.

Alternative Testing Strategies for Nanomaterials: State of the Science and Considerations for Risk Analysis

The rapid growth of the nanotechnology industry has warranted equal progress in the nanotoxicology and risk assessment fields. In vivo models have traditionally been used to determine human and environmental risk for chemicals; however, the use of these tests has limitations, and there are global appeals to develop reliable alternatives to animal testing. Many have investigated the use of alternative (nonanimal) testing methods and strategies have quickly developed and resulted in the generation of large toxicological data sets for numerous nanomaterials (NMs). Due to the novel physicochemical properties of NMs that are related to surface characteristics, the approach toward toxicity test development has distinct considerations from traditional chemicals, bringing new requirements for adapting these approaches for NMs. The methodical development of strategies that combine multiple alternative tests can be useful for predictive NM risk assessment and help screening-level decision making. This article provides an overview of the main developments in alternative methods and strategies for reducing uncertainty in NM risk assessment, including advantages and disadvantages of in vitro, ex vivo, and in silico methods, and examples of existing comprehensive strategies. In addition, knowledge gaps are identified toward improvements for experimental and strategy design, specifically highlighting the need to represent realistic exposure scenarios and to consider NM-specific concerns such as characterization, assay interferences, and standardization. Overall, this article aims to improve the reliability and utility of alternative testing methods and strategies for risk assessment of manufactured NMs.

Advancing Risk Analysis for Nanoscale Materials: Report from an International Workshop on the Role of Alternative Testing Strategies for Advancement

The Society for Risk Analysis (SRA) has a history of bringing thought leadership to topics of emerging risk. In September 2014, the SRA Emerging Nanoscale Materials Specialty Group convened an international workshop to examine the use of alternative testing strategies (ATS) for manufactured nanomaterials (NM) from a risk analysis perspective. Experts in NM environmental health and safety, human health, ecotoxicology, regulatory compliance, risk analysis, and ATS evaluated and discussed the state of the science for in vitro and other alternatives to traditional toxicology testing for NM. Based on this review, experts recommended immediate and near-term actions that would advance ATS use in NM risk assessment. Three focal areas-human health, ecological health, and exposure considerations-shaped deliberations about information needs, priorities, and the next steps required to increase confidence in and use of ATS in NM risk assessment. The deliberations revealed that ATS are now being used for screening, and that, in the near term, ATS could be developed for use in read-across or categorization decision making within certain regulatory frameworks. Participants recognized that leadership is required from within the scientific community to address basic challenges, including standardizing materials, protocols, techniques and reporting, and designing experiments relevant to real-world conditions, as well as coordination and sharing of large-scale collaborations and data. Experts agreed that it will be critical to include experimental parameters that can support the development of adverse outcome pathways. Numerous other insightful ideas for investment in ATS emerged throughout the discussions and are further highlighted in this article.

Estimated cost per HIV infection diagnosed through routine HIV testing offered in acute general medical admission units and general practice settings in England

OBJECTIVES

Following national guidelines to expand HIV testing in high-prevalence areas in England, a number of pilot studies were conducted in acute general medical admission units (ACUs) and general practices (GPs) to assess the feasibility and acceptability of testing in these settings. The aim of this study was to estimate the cost per HIV infection diagnosed through routine HIV testing in these settings.

METHODS

Resource use data from four 2009/2010 Department of Health pilot studies (two ACUs; two GPs) were analysed. Data from the pilots were validated and supplemented with information from other sources. We constructed possible scenarios to estimate the cost per test carried out through expanded HIV testing in ACUs and GPs, and the cost per diagnosis.

RESULTS

In the pilots, cost per test ranged from £8.55 to £13.50, and offer time and patient uptake were 2 minutes and 90% in ACUs, and 5 minutes and 60% in GPs, respectively. In scenario analyses we fixed offer time, diagnostic test cost and uptake rate at 2 minutes, £6 and 80% for ACUs, and 5 minutes, £9.60 and 40% for GPs, respectively. The cost per new HIV diagnosis at a positivity of 2/1000 tests conducted was £3230 in ACUs and £7930 in GPs for tests performed by a Band 3 staff member, and £5940 in ACUs and £18 800 in GPs for tests performed by either hospital consultants or GPs.

CONCLUSIONS

Expanded HIV testing may be more cost-efficient in ACUs than in GPs as a consequence of a shorter offer time, higher patient uptake, higher HIV positivity and lower diagnostic test costs. As cost per new HIV diagnosis reduces at higher HIV positivity, expanded HIV testing should be promoted in high HIV prevalence areas.

Evaluating the toxicity of hydroxyapatite nanoparticles in catfish cells and zebrafish embryos

The toxicity of needle-(nHA-ND) and rod-shaped (nHA-RD) hydroxyapatite (HA) nanoparticles is evaluated in vitro on catfish B-cells (3B11) and catfish T-cells (28s.3) and in vivo on zebrafish embryos to determine if biological effects are similar to the effects seen in mammalian in vitro systems. Neither nHA-ND nor nHA-RD affect cell viability at concentrations of 10 to 300 μg mL(-1) . However, 30 μg mL(-1) needle-shaped nHA lower metabolic activity of the cells. Axial deformations are seen in zebrafish exposed to 300 μg mL(-1) needle shaped nHA after 120 h. For the first time, nHA is reported to cause zebrafish hatching delay. The lowest concentration (3 μg mL(-1) ) of both types of nHA cause the highest hatching inhibition and needle-shaped nHA exposed zebrafish exhibit the lowest hatch at 72 h post fertilization.

Silver nanoparticles inhibit sodium uptake in juvenile rainbow trout (Oncorhynchus mykiss)

The silver ion (Ag(+)) is well documented to be a potent inhibitor of sodium (Na(+)) transport in fish. However, it has not been determined whether silver nanoparticles (Ag NPs) elicit this same effect and, if so, if the NP itself and/or the dissociation of ionic Ag(+) causes this effect. Citrate-capped Ag NPs were dialyzed in water to determine the dissolution rate of ionic Ag(+) from the NPs and the maximum concentration of free Ag(+) released from the NPs was used as a paired Ag(+) control to distinguish NP effects from ionic metal effects. The maximum concentration of ionic Ag(+) released from these NPs over 48 h was 0.02 μg l(-1). Juvenile rainbow trout were exposed to 1.0 mg l(-1) citrate-capped Ag NPs and dialyzed citrate-capped Ag NPs or 10 μg l(-1) and 0.02 μg l(-1) ionic Ag(+) (as AgNO(3)) as controls. Both nondialyzed and dialyzed Ag NPs and 10 μg l(-1) ionic Ag(+) significantly inhibited unidirectional Na(+) influx by over 50% but had no effect on unidirectional Na(+) efflux. Na(+),K(+)-ATPase was significantly inhibited by the Ag NPs with no discernible effect on carbonic anhydrase activity. This study is the first to show that sodium regulation is disrupted by the presence of citrate-capped Ag NPs, and the results suggest that there are nanospecific effects.

Gill morphology of the mangrove killifish (Kryptolebias marmoratus) is plastic and changes in response to terrestrial air exposure

Amphibious mangrove killifish, Kryptolebias marmoratus (formerly Rivulus marmoratus), are frequently exposed to aerial conditions in their natural environment. We tested the hypothesis that gill structure is plastic and that metabolic rate is maintained in response to air exposure. During air exposure, when gills are no longer functional, we predicted that gill surface area would decrease. In the first experiment, K. marmoratus were exposed to either water (control) or air for 1 h, 1 day, 1 week, or 1 week followed by a return to water for 1 week (recovery). Scanning electron micrographs (SEM) and light micrographs of gill sections were taken, and morphometric analyses of lamellar width, lamellar length and interlamellar cell mass (ILCM) height were performed. Following 1 week of air exposure, SEM indicated that there was a decrease in lamellar surface area. Morphometric analysis of light micrographs revealed that there were significant changes in the height of the ILCM, but there were no significant differences in lamellae width and length between any of the treatments. Following 1 week of recovery in water, the ILCM regressed and gill lamellae were similar to control fish, indicating that the morphological changes were reversible. In the second experiment, V(CO(2)) was measured in fish continuously over a 5-day period in air and compared with previous measurements of oxygen uptake (V(O(2))) in water. V(CO(2)) varied between 6 and 10 micromol g(-1) h(-1) and was significantly higher on days 3, 4 and 5 relative to days 1 and 2. In contrast to V(O(2)) in water, V(CO(2)) in air showed no diurnal rhythm over a 24 h period. These findings indicate that K. marmoratus remodel their gill structures in response to air exposure and that these changes are completely reversible. Furthermore, over a similar time frame, changes in V(CO(2)) indicate that metabolic rate is maintained at a rate comparable to that of fish in water, underlying the remarkable ability of K. marmoratus to thrive in both aquatic and terrestrial habitats.

Molecular analysis of HLA-B in the Malaysian aborigines

We have examined 56 unrelated individuals from Malaysian aborigines for their DNA polymorphism of the HLA-B gene by sequence specific oligonucleotide probe (SSO) method. Using the SSO hybridization, we found that one specific DNA allele with a B*1513 like pattern of epitope combination (ECB1513) was dominant among the Melayu Asli (Af = 41.9%) and the Senoi (Af = 24%). To determine the nucleotide sequences of ECB1513, a DNA fragment spanning from the beginning of exon 1 to the middle of exon 4 of the HLA-B gene was amplified by polymerase chain reaction (PCR) from two ECB1513 positive individuals, and the PCR products were cloned and sequenced. This sequencing analysis confirmed that ECB1513 was identical to HLA-B*1513 in exon 1, 2, 3, and 4. Amino acid sequence of this major allele, HLA-B*1513, in the aborigines especially around the peptide binding groove (B and F pockets), was compared with that of African B*5301 that had been suggested to confer resistance to malaria infection in Africa. The amino acid residues composing of the F pocket were completely identical in B*1513 and B*5301. These observations suggest that a common environmental factor, the malaria infection, might have independently enhanced the selection of functional change in the polymorphic portion of HLA-B gene in Africa and in South-East Asia.

HLA antigens in Malay patients with systemic lupus erythematosus

Many studies have shown an association between human leucocyte antigens (HLA) and systemic lupus erythematosus (SLE) in the various study populations. Although SLE is not an uncommon disease in the Malaysian Archipelago, and appears to affect all three major racial groups equally (i.e. Southern Chinese, Malays and Southern Indians), very little information is available on the HLA profiles in the two latter groups. In phase I of our study of the HLA profiles in Malaysian SLE patients, the HLA phenotypes (class I: A, B, C; Class II: DR, DQ) of Malay patients with confirmed SLE and 91 normal Malay controls were determined using the microcytotoxicity assay. The strong association between DR (RR 3.28, P = 0.008) concurs with that reported among Chinese and Japanese populations. Moderate to strong associations with HLA-B 7 (RR 4.99, P = 0.02) and Cw 7 (RR 2.94, P = 0.003) were also found. We believe this is the first report of the association of HLA and SLE in the Malay population.

Seroreactivity to syphilis in Malaysian blood donors and expectant mothers

Seroreactivity to syphilis is high among Malaysian blood donors and expectant mothers indicating a high degree of treponemal infection. Further epidemiological studies are required to ascertain what proportion of these could be syphilis and what porportion yaws. Blood donors hava a higher reactivity rate than expectant mothers, the reasons probably being soical. The titres obtained in the VDRL test appear to have a relation to FTA-ABS reactivity although this is not to say treponematosis can be excluded on the basis of low titre VDRL results.