Effects of Ionizing Radiation on Plastic Food Packaging Materials: A Review

1993 ◽  
Vol 56 (11) ◽  
pp. 991-997 ◽  
Author(s):  
RAINER BUCHALLA ◽  
CHRISTIAN SCHÜTTLER ◽  
KLAUS WERNER BÖGL
Keyword(s):  
Ionizing Radiation ◽  
Food Packaging ◽  
Safety Evaluation ◽  
Food Irradiation ◽  
Packaging Materials ◽  
Volatile Products ◽  
History Of ◽  
Radiation Induced ◽  
Induced Changes ◽  
Physical Changes

Irradiation of prepackaged food causes chemical and physical changes in plastic packaging materials. The effects of ionizing radiation on these materials have been studied for almost 40 years; the respective literature is reviewed to provide the basis for a safety evaluation of plastics for use in food irradiation. Permeability of plastic films is generally not affected; deterioration of mechanical properties, that may occur with certain polymers, can usually be controlled with adequate stabilizers; and changes in infrared and UV/VIS spectra are slight at food irradiation doses. Gaseous radiolysis products include hydrogen, methane, CO2, CO, hydrocarbons, and for chlorine-containing polymers, hydrogen chloride. A range of volatile products, mainly hydrocarbons, alcohols, aldehydes, ketones, and carboxylic acids, has been characterized for low density polyethylene and polypropylene, other important materials, e.g., polystyrene and poly(vinyl chloride), are less well-investigated. Comparatively little is known on the effect of irradiation on multilayer structures. Radiation-induced changes are shown to depend on the chemical structure of the polymer, on the composition (additives) and processing history of the plastic, and on the irradiation conditions.

Abstract 127: Radiosurgery for Unruptured Intervention-Naïve Pediatric Brain Arteriovenous Malformations

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Ching-jen Chen ◽  
Cheng-Chia Lee ◽  
Hideyuki Kano ◽  
Kathryn Kearns ◽  
Dale Ding ◽  
...  
Keyword(s):  
Primary Endpoint ◽  
Arteriovenous Malformations ◽  
Pediatric Population ◽  
Study Cohort ◽  
Brain Arteriovenous Malformations ◽  
History Of ◽  
Radiation Induced ◽  
Induced Changes ◽  
Pediatric Brain ◽  
Stroke Death

Background and Purpose: To evaluate, in a multicenter, retrospective cohort study, the outcomes after stereotactic radiosurgery (SRS) for unruptured, intervention-naïve pediatric brain arteriovenous malformations (AVM). Methods: We retrospectively analyzed the International Radiosurgery Research Foundation pediatric AVM database from 1987-2018. Pediatric patients with unruptured, previously untreated AVMs who underwent SRS were included. The primary endpoint was a composite of hemorrhagic stroke, death, or permanently symptomatic radiation-induced changes (RIC). Results: The study cohort comprised 101 patients (mean follow-up 80.8 months). The primary endpoint occurred in 14%, comprising hemorrhage stroke, death, and permanent RIC in 6%, 3%, and 8%, respectively. Estimated probabilities of the primary endpoint were 5.2%, 10.8%, and 23.0% at 2, 5, and 10 years, respectively (Figure 1). Estimated probabilities of AVM obliteration at 5 and 10 years were 64% and 82%, respectively (Figure 2). Single SRS treatment (p=0.007) and higher margin dose (p=0.005) were predictors of obliteration. Subgroup analysis of Spetzler-Martin grade I-III AVMs estimated primary endpoint probabilities of 3.7%, 8.4%, and 18.7% at 2, 5 and 10 years, respectively. Conclusion: Treatment of unruptured, intervention-naïve AVMs in the pediatric population with SRS carries an approximately 2% annual risk of morbidity and mortality, which appears to plateau after 10 years. The poorly described natural history of pediatric AVMs makes any comparison of SRS versus conservative management imperfect. However, due to the young age at diagnosis and excessive cumulative life hemorrhage risk of an untreated AVM in a child, SRS is likely to have a favorable long-term risk-benefit profile for appropriately selected unruptured pediatric AVMs.

Effect of the type of ionizing radiation on the radiation-induced changes in petroleum oils

1969 ◽  
Vol 5 (1) ◽  
pp. 62-65
Author(s):  
A. D. Stukin ◽  
G. I. Shor ◽  
V. A. Gorbach ◽  
A. G. Ryaboshapko
Keyword(s):  
Ionizing Radiation ◽  
Radiation Induced ◽  
Induced Changes ◽  
Petroleum Oils

Ionizing radiation-induced changes in chlorinated hydrocarbons

1974 ◽  
Vol 5 (9) ◽  
pp. 143-144 ◽  
Author(s):  
A.R. Ceurvels ◽  
J. DerHovanesian ◽  
J. Kaylor
Keyword(s):  
Ionizing Radiation ◽  
Chlorinated Hydrocarbons ◽  
Radiation Induced ◽  
Induced Changes

Effects of Ionizing Radiation on Plastic Food Packaging Materials: A Review

1993 ◽  
Vol 56 (11) ◽  
pp. 998-1005 ◽  
Author(s):  
RAINER BUCHALLA ◽  
CHRISTIAN SCHÜTTLER ◽  
KLAUS WERNER BÖGL
Keyword(s):  
Ionizing Radiation ◽  
Gamma Irradiation ◽  
Food Packaging ◽  
Degradation Products ◽  
Packaging Materials ◽  
Tin Compounds ◽  
Global Migration ◽  
Food Simulants ◽  
Phenol Antioxidants ◽  
Plastics Additives

Increased “global” migration into food simulants has been described as a consequence of irradiation, particularly with fatty media; development of off-odors and taint transfer into food simulants have been observed with various plastics. Additives, especially antioxidants, are destroyed during irradiation, and increased “specific” migration values have been observed under certain circumstances. Organotin stabilizers in PVC are ultimately degraded to SnCl4, and increased migration of tin compounds was observed after gamma irradiation. Degradation products of phenol antioxidants, that were also found as migrants, have only recently been identified; some of these structures seem to be radiation specific.

scholarly journals Endoscopic Ultrasound-Guided Fine Needle Aspiration (EUS-FNA) Diagnosis of Recurrent Anal Cancer after Chemoradiation and Negative Forceps Biopsies: A Case Report

2009 ◽  
Vol 3 ◽  
pp. CMO.S993
Author(s):  
Julia Leblanc ◽  
Pradermchai Kongkam
Keyword(s):  
Rectal Wall ◽  
Cell Cancer ◽  
Digital Rectal Examination ◽  
Dentate Line ◽  
Needle Aspiration ◽  
Endoscopic Biopsy ◽  
Rectal Mass ◽  
History Of ◽  
Radiation Induced ◽  
Induced Changes

A 69-year-old woman with a history of uT2 N0 post-treated anal squamous cell cancer (SCC) presented for EUS for perianal pain. Two months prior, a digital rectal examination was significant for an indurated lesion on the left lateral rectal wall just proximal to the dentate line. A sigmoidoscopy revealed mild narrowing of the anal canal and an ulcerated friable mucosa in the same area. A biopsy demonstrated ulceration without malignancy. EUS showed a hypoechoic, non-circumferential, left-sided distal rectal mass. EUS-FNA was performed. Cytology demonstrated poorly differentiated SCC. This was confirmed by subsequent surgical resection. While endoscopic biopsy of suspected anal recurrences is usually sufficient, histologic or cytologic confirmation are necessary, as radiation-induced changes are difficult to differentiate from tumor recurrence. This case demonstrates that EUS-FNA is useful in surveillance of anal SCC when there is a high clinical suspicion of recurrence.

Radiation-induced meningioma: a descriptive study of 253 cases

2002 ◽  
Vol 97 (5) ◽  
pp. 1078-1082 ◽  
Author(s):  
Siegal Sadetzki ◽  
Pazit Flint-Richter ◽  
Tehila Ben-Tal ◽  
Dvora Nass
Keyword(s):  
Ionizing Radiation ◽  
Present Report ◽  
Previous History ◽  
Latency Period ◽  
Content Type ◽  
Established Risk Factor ◽  
History Of ◽  
Radiation Induced ◽  
The Mean ◽  
Fine Print

Object. Ionizing radiation is the only established risk factor recognized today in the causation of meningioma. The aim of the present report is to describe the demographic and clinical characteristics of a large series of 253 patients with radiation-induced meningiomas (RIMs). These parameters were compared with those of 41 patients with meningiomas in whom there was no previous history of irradiation (non-RIM group) and with other series of patients presented in the literature. Methods. The cases of RIM were recruited from a cohort of appproximately 11,000 individuals who had been treated with ionizing radiation during childhood for tinea capitis and from a group of individuals who, as adults, applied for compensation because of that treatment. The non-RIM group was identified through the Israeli Cancer Registry. Exposure to radiation was carefully validated among all cases of RIM and absence of previous irradiation was verified for all patients in the non-RIM group. Significantly, a lower patient age at diagnosis, higher prevalence of calvarial tumors, higher proportion of multiple meningiomas, and a nonsignificant higher recurrence rate were observed among patients with RIM compared with the non-RIM group. The mean latency period from date of radiation exposure to development of a meningioma among the RIM group was approximately 36 years. Conclusions. The findings of this study agree with those of other studies indicating the demographic, clinical, and even genetic variability between RIM and non-RIM cases. The existence of two different subtypes of meningiomas may have profound implications for screening, early diagnosis, and therapy of meningiomas.

Effect of Prior Hemorrhage on Intracranial Arteriovenous Malformation Radiosurgery Outcomes

2014 ◽  
Vol 39 (1) ◽  
pp. 53-62 ◽  
Author(s):  
Dale Ding ◽  
Chun-Po Yen ◽  
Robert M. Starke ◽  
Zhiyuan Xu ◽  
Jason P. Sheehan
Keyword(s):  
Gamma Knife Radiosurgery ◽  
Latency Period ◽  
Time Interval ◽  
Intracranial Arteriovenous Malformation ◽  
Complete Obliteration ◽  
History Of ◽  
Radiation Induced ◽  
Prescription Dose ◽  
The Mean ◽  
Induced Changes

Background: Intracerebral hemorrhage is simultaneously the most frequent and most debilitating manifestation of intracranial arteriovenous malformations (AVM), but its impact on success and complications of radiosurgery has not been rigorously assessed. In this case-control study, we define the effect of prior hemorrhage on AVM radiosurgery outcomes. Methods: From a prospective, institutional database of 1,400 AVM patients treated with Gamma Knife radiosurgery, unruptured and ruptured AVMs were matched in a 1:1 fashion, blinded to outcome, based on patient demographics, prior embolization (26.6% of each cohort), AVM size (mean volume of unruptured AVMs 3.7 cm3 versus ruptured AVMs 3.5 cm3, p = 0.195), Spetzler-Martin grade (Grade I 17.0%, Grade II 37.8%, Grade III 34.8%, Grade IV 10.4% for each cohort), and radiosurgical treatment parameters (mean prescription dose for unruptured AVMs 20.9 Gy versus ruptured AVMs 21.0 Gy, p = 0.837). There were 270 patients in each cohort. Matched statistical analyses were used to compare the baseline characteristics, obliteration rates, post-radiosurgery latency period hemorrhage risks, and incidences of radiation-induced changes (RIC) between the two cohorts. Results: The actuarial obliteration rates of the two cohorts were similar (unruptured AVMs: 38, 58, and 76% at 3, 5, 10 years, respectively; ruptured AVMs: 40, 60, and 73% at 3, 5, 10 years, respectively; p = 0.592). However, for embolized AVMs, complete obliteration was more likely to be achieved in unruptured lesions (unruptured AVMs: 25, 32, and 54% at 3, 5, 10 years, respectively; ruptured AVMs: 18, 27, and 42% at 3, 5, 10 years, respectively; p = 0.038). Prior AVM rupture resulted in a higher annual risk of post-radiosurgery latency period hemorrhage (ruptured AVMs 2.3% versus unruptured AVMs 1.1%, p = 0.025) but a lower rate of cumulative and symptomatic RIC (cumulative RIC: ruptured AVMs 30.4% versus unruptured AVMs 48.9%, p < 0.0001; symptomatic RIC: ruptured AVMs 7.0% versus unruptured AVMs 12.2%, p = 0.041, respectively). The rates of permanent RIC were similar between the unruptured (2.2%) and ruptured (1.9%) AVM cohorts (p = 0.761). The mean time interval to onset of RIC (unruptured AVMs 13.3 months versus ruptured AVMs 12.1 months, p = 0.783), and the mean duration of RIC (unruptured AVMs 22.0 months versus ruptured AVMs 21.7 months, p = 0.599) were not significantly different between the two cohorts. Conclusions: Prior AVM rupture significantly alters the risk of latency period hemorrhage and RIC following radiosurgery. These effects should be taken into consideration with the multidisciplinary management of AVM patients. Radiosurgery does not significantly alter the natural history of the hemorrhage risks of unruptured and ruptured AVMs unless obliteration is achieved.

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